feat(stealth): earn and equip the Eye of True Seeing

Add independent eight-hour Night Vision progression, save-gated crafting and holder eligibility, authenticated helmet items and guarded inventory movement. Verify source attribution, native item/recipe/event adapters and actual plugin lifecycle. Drain final state asynchronously and reject stale lifecycle callbacks. Per-viewer revelation remains the next story; no deployment is included.

.gitea/workflows/ci.yml

@@ -17,7 +17,7 @@ jobs:
         uses: actions/setup-java@v4
         with:
           distribution: temurin
-          java-version: 17
+          java-version: 25
           cache: gradle
 
       - name: Validate conventional commits
@@ -35,6 +35,6 @@ jobs:
       - name: Upload development artifact
         uses: actions/upload-artifact@v3
         with:
-          name: spigot-stealth-${{ github.sha }}
+          name: purpur-stealth-${{ github.sha }}
           path: build/libs/*.jar
           if-no-files-found: error

.gitea/workflows/release.yml

@@ -21,7 +21,7 @@ jobs:
         uses: actions/setup-java@v4
         with:
           distribution: temurin
-          java-version: 17
+          java-version: 25
           cache: gradle
 
       - name: Set up Node.js
@@ -86,8 +86,8 @@ jobs:
         if: steps.release.outputs.created == 'true'
         uses: actions/upload-artifact@v3
         with:
-          name: spigot-stealth-${{ steps.release.outputs.version }}
+          name: purpur-stealth-${{ steps.release.outputs.version }}
-          path: build/libs/spigot-stealth-${{ steps.release.outputs.version }}.jar
+          path: build/libs/purpur-stealth-${{ steps.release.outputs.version }}.jar
           if-no-files-found: error
 
       - name: Create Gitea release and upload plugin
@@ -101,7 +101,7 @@ jobs:
           PREVIOUS_TAG: ${{ steps.previous_tag.outputs.value }}
         run: |
           api_url="${GITEA_SERVER_URL}/api/v1"
-          jar="build/libs/spigot-stealth-${VERSION}.jar"
+          jar="build/libs/purpur-stealth-${VERSION}.jar"
           export RELEASE_BODY
           if [ -n "$PREVIOUS_TAG" ]; then
             RELEASE_BODY=$(git log --pretty='format:- %s (%h)' "${PREVIOUS_TAG}..HEAD")
@@ -138,4 +138,4 @@ jobs:
             -H "Authorization: token ${GITEA_TOKEN}" \
             -H "Content-Type: application/octet-stream" \
             --data-binary "@${jar}" \
-            "${api_url}/repos/${REPOSITORY}/releases/${release_id}/assets?name=spigot-stealth-${VERSION}.jar"
+            "${api_url}/repos/${REPOSITORY}/releases/${release_id}/assets?name=purpur-stealth-${VERSION}.jar"

AGENTS.md

@@ -1,53 +1,9 @@
-# Repository Agent Guidance
+# purpur-stealth agent entrypoint
 
-## User-story-driven development
+The canonical stories, engineering guidance, and **all process documents** are in the private [SoMC OKF wiki](https://git.garvis.dev/dmg/somc-okf/src/branch/main/index.md).
 
-The `design/` directory is the OKF v0.1 product record for this repository. Use user stories to plan, implement, verify, and track all behavior.
+Before work, read the sibling `../somc-okf/index.md`, `../somc-okf/processes/index.md`, `../somc-okf/projects/purpur-stealth/index.md`, `engineering.md` in that project section, and relevant `../somc-okf/user-stories/purpur-stealth/` stories. Also follow the parent workspace `AGENTS.md` when present.
 
-Before changing behavior:
+For standalone checkouts, start at the [project page](https://git.garvis.dev/dmg/somc-okf/src/branch/main/projects/purpur-stealth/index.md) and [shared process](https://git.garvis.dev/dmg/somc-okf/src/branch/main/processes/development.md). Obtain wiki access before feature work; do not recreate a local knowledge bundle. Source builds do not require private wiki access.
 
-1. Read `design/index.md` and every story related to the requested behavior.
+Development follows [Development cycle](https://git.garvis.dev/dmg/somc-okf/src/branch/main/runbooks/development-cycle.md): approved stories, failing tests, passing implementation, verification, then source/wiki commit and push. GitOps updates are committed locally **without pushing**; only [Do release](https://git.garvis.dev/dmg/somc-okf/src/branch/main/runbooks/do-release.md) authorizes a reviewed GitOps push.
-2. Draft updates to an existing story or create a new `design/user-stories/us-NNN-short-name.md` story before implementation.
-3. Define observable acceptance criteria using user or operator language.
-4. Present the relevant new or updated stories and acceptance criteria to the user for review, and wait for explicit confirmation before changing implementation code.
-5. Incorporate requested story changes before proceeding.
-6. Set story status to `in-progress` while approved implementation is incomplete.
-
-While implementing:
-
-1. Work in vertical slices against the documented acceptance criteria.
-2. Add tests for important behavior before implementation when practical.
-3. Keep implementation references and related-story links current.
-4. Do not mark an acceptance criterion complete until the behavior exists and has been validated.
-
-Before completing or committing:
-
-1. Set a completed story status to `done` only when all acceptance criteria are complete and verified.
-2. Check completed acceptance criteria and record validation evidence where appropriate.
-3. Update `design/index.md` and `design/user-stories/index.md` whenever stories are added, renamed, moved, or materially reclassified.
-4. Add a high-level entry to `design/log.md` under the verified current date.
-5. Run OKF validation along with relevant Gradle tests, lint checks, and builds.
-
-## OKF conventions
-
-- Every non-reserved Markdown file in `design/` must have YAML frontmatter with a non-empty `type`.
-- User stories use `type: User Story` and include `status`, `title`, and `description`.
-- Allowed story statuses are `backlog`, `in-progress`, and `done`.
-- Every user story includes an acceptance-criteria section using Markdown task-list items.
-- `design/index.md` and `design/log.md` are reserved OKF files and follow the OKF index/log structures.
-- Store user stories in `design/user-stories/` and keep their catalog current.
-- Use standard Markdown links and keep repository-local links valid when files move.
-- Preserve unknown frontmatter extensions.
-
-## Java and Spigot development
-
-- Use the Java version and Spigot API version declared by the Gradle build.
-- Treat compiler warnings as errors.
-- Prefer test-first development for domain rules and state transitions when practical.
-- Run `./gradlew clean check jar` before completing implementation work.
-- Keep Bukkit event handlers thin and move testable game rules into focused domain services.
-- Do not perform blocking file or network operations on the server tick thread.
-
-## Timestamps
-
-Always run `date +%Y-%m-%d` before adding or updating dates in stories or the design log. Use RFC 3339 UTC timestamps (`YYYY-MM-DDTHH:MM:SSZ`) when a date-time is required. Never guess dates.

README.md

@@ -0,0 +1,33 @@
+# Purpur Stealth
+
+Progression-gated identity concealment for Purpur 26.2 build 2618, built and tested with Java 25. ProtocolLib 5.4.0 is required.
+
+## Build
+
+```sh
+./gradlew clean check jar
+```
+
+Artifacts are written to `build/libs/purpur-stealth-<version>.jar`. Gitea CI verifies pushes/pull requests; approved main-branch conventional commits drive versioned releases. The distribution tests inspect the built JAR, embedded version/runtime identity, Java 25 bytecode, and workflow naming.
+
+## Eye of True Seeing
+
+Earn a separate, personal unlock through eight cumulative online hours of Night Vision from directly drunk potions. Splash/lingering potions, commands, plugins and other sources do not count. Rejected and cosmetic-only replacements do not change attribution. Unattributed restored effects cannot inherit the drink timer; a new effective drink can start a new interval. Offline time is excluded.
+
+After the unlock is saved, craft an **Eye of True Seeing** with eight Netherite Blocks around an Eye of Ender. Right-click an authenticated Eye in either hand to move it into an empty helmet slot. Existing helmets are not replaced. Traded Eyes still require the holder's own saved unlock; renamed ordinary Eyes do not qualify. Automated crafters cannot bypass progression. Vanilla handles crafting ingredient consumption.
+
+**Local name/body revelation is separate US-008 work and is not implemented by this acquisition story.** Eligibility is checked even for an Eye manually placed in the helmet slot.
+
+Eye records are independently UUID-keyed in `plugins/SpigotStealth/state.yml` (schema 2). Legacy Stealth records and extension fields are preserved. Crafting/use wait for successful save acknowledgement. Shutdown queues a final snapshot without blocking the tick thread, and initialization callbacks cannot revive a disabled or superseded lifecycle. Unacknowledged progress at abrupt process/power loss is not guaranteed.
+
+`check` includes `nativeStealthTest`, which downloads SHA-256-pinned Purpur 2618, patches it without starting a listening server, and exercises real potion events, items, recipes, event dispatch and plugin lifecycle with external platform doubles. Live-client appearance and gameplay checks remain separate follow-ups.
+
+## Migration compatibility
+
+The repository and checkout are now `purpur-stealth` (previously remote `spigot-stealth`, local `spigot-invisibilty`). Runtime identity remains **SpigotStealth**, including `plugins/SpigotStealth/`, the existing Java entrypoint/packages, command names, `spigotstealth` permission/namespace identifiers, and persisted progression/session data. Java 17 is no longer supported for new builds or artifacts.
+
+Replace the old plugin JAR when installing the new distribution; never load both JARs together. Old tags and `spigot-stealth-*` release assets are preserved. Repository rename redirects have been checked against the previously deployed v1.5.0 download. Publishing a release does not authorize deployment.
+
+The v2.0.0 migration itself left the Eye, combat reveal and concealed-chat stories pending. Subsequent Eye acquisition work is described above; Eye revelation, combat reveal and system-chat routing remain separate unfinished stories. Runtime plugin metadata is unchanged.
+
+See the [canonical project](https://git.garvis.dev/dmg/somc-okf/src/branch/main/projects/purpur-stealth/index.md), [stories](https://git.garvis.dev/dmg/somc-okf/src/branch/main/user-stories/purpur-stealth/index.md), and [development cycle](https://git.garvis.dev/dmg/somc-okf/src/branch/main/runbooks/development-cycle.md).

build.gradle.kts

@@ -1,3 +1,6 @@
+import java.net.URI
+import java.security.MessageDigest
+
 plugins {
     java
 }
@@ -9,24 +12,25 @@ version = providers.gradleProperty("releaseVersion")
 
 repositories {
     mavenCentral()
-    maven("https://hub.spigotmc.org/nexus/content/repositories/snapshots/")
+    maven("https://repo.purpurmc.org/snapshots/")
 }
 
 java {
     toolchain {
-        languageVersion = JavaLanguageVersion.of(17)
+        languageVersion = JavaLanguageVersion.of(25)
     }
 }
 
 tasks.withType<JavaCompile>().configureEach {
-    options.compilerArgs.addAll(listOf("-Xlint:all", "-Werror"))
+    // Retain the supported legacy Bukkit surface for runtime identity compatibility.
+    options.compilerArgs.addAll(listOf("-Xlint:all,-deprecation,-removal", "-Werror"))
 }
 
 dependencies {
-    compileOnly("org.spigotmc:spigot-api:26.2-R0.1-SNAPSHOT")
+    compileOnly("org.purpurmc.purpur:purpur-api:26.2.build.2618-stable")
     compileOnly("net.dmulloy2:ProtocolLib:5.4.0")
 
-    testImplementation("org.spigotmc:spigot-api:26.2-R0.1-SNAPSHOT")
+    testImplementation("org.purpurmc.purpur:purpur-api:26.2.build.2618-stable")
     testImplementation("net.dmulloy2:ProtocolLib:5.4.0")
     testImplementation(platform("org.junit:junit-bom:5.13.4"))
     testImplementation("org.junit.jupiter:junit-jupiter")
@@ -37,8 +41,65 @@ dependencies {
 
 tasks.test {
     useJUnitPlatform()
+    dependsOn(tasks.jar)
+    systemProperty("distribution.jar", tasks.jar.get().archiveFile.get().asFile.absolutePath)
+    systemProperty("distribution.version", project.version.toString())
 }
 
+// Exercise real potion events, item components and recipes without starting a listening server.
+val stealthRuntime = layout.buildDirectory.dir("stealth-runtime")
+val downloadStealthRuntime = tasks.register("downloadStealthRuntime") {
+    val launcher = stealthRuntime.map { it.file("purpur-26.2-2618.jar") }
+    outputs.file(launcher)
+    doLast {
+        val file = launcher.get().asFile
+        file.parentFile.mkdirs()
+        val connection = URI("https://api.purpurmc.org/v2/purpur/26.2/2618/download").toURL().openConnection()
+        connection.connectTimeout = 30_000
+        connection.readTimeout = 120_000
+        val bytes = connection.getInputStream().use { it.readBytes() }
+        val digest = MessageDigest.getInstance("SHA-256").digest(bytes).joinToString("") { "%02x".format(it) }
+        check(digest == "4a32d046a118804d89ca74ba89b798c98f6d8d1f310c18077ac573597049de31") {
+            "Purpur 2618 checksum mismatch"
+        }
+        file.writeBytes(bytes)
+    }
+}
+val prepareStealthRuntime = tasks.register<JavaExec>("prepareStealthRuntime") {
+    dependsOn(downloadStealthRuntime)
+    javaLauncher = javaToolchains.launcherFor { languageVersion = JavaLanguageVersion.of(25) }
+    classpath = files(stealthRuntime.map { it.file("purpur-26.2-2618.jar") })
+    mainClass = "io.papermc.paperclip.Main"
+    jvmArgs("-Dpaperclip.patchonly=true")
+    workingDir(stealthRuntime)
+    outputs.dir(stealthRuntime.map { it.dir("versions") })
+    outputs.dir(stealthRuntime.map { it.dir("libraries") })
+}
+val nativeTest = sourceSets.create("nativeTest")
+dependencies {
+    add(nativeTest.implementationConfigurationName, platform("org.junit:junit-bom:5.13.4"))
+    add(nativeTest.implementationConfigurationName, "org.junit.jupiter:junit-jupiter")
+    add(nativeTest.implementationConfigurationName, "org.mockito:mockito-core:5.18.0")
+    add(nativeTest.implementationConfigurationName, "net.dmulloy2:ProtocolLib:5.4.0")
+    add(nativeTest.compileOnlyConfigurationName, "org.jetbrains:annotations:26.0.2")
+    add(nativeTest.compileOnlyConfigurationName, "org.checkerframework:checker-qual:3.49.2")
+    add(nativeTest.runtimeOnlyConfigurationName, "org.junit.platform:junit-platform-launcher")
+}
+val nativeRuntimeJars = files(fileTree(stealthRuntime) {
+    include("versions/**/*.jar", "libraries/**/*.jar")
+}).builtBy(prepareStealthRuntime)
+nativeTest.compileClasspath += sourceSets.main.get().output + nativeRuntimeJars
+nativeTest.runtimeClasspath += sourceSets.main.get().output + nativeRuntimeJars
+val nativeStealthTest = tasks.register<Test>("nativeStealthTest") {
+    description = "Runs native Purpur adapter regressions without starting a server"
+    testClassesDirs = nativeTest.output.classesDirs
+    classpath = nativeTest.runtimeClasspath
+    useJUnitPlatform()
+    maxHeapSize = "1G"
+    workingDir(stealthRuntime)
+}
+tasks.check { dependsOn(nativeStealthTest) }
+
 val pluginVersion = version
 
 tasks.processResources {
@@ -46,11 +107,3 @@ tasks.processResources {
         expand("version" to pluginVersion)
     }
 }
-
-tasks.register<Exec>("validateOkf") {
-    commandLine("./scripts/validate-okf.sh")
-}
-
-tasks.check {
-    dependsOn("validateOkf")
-}

design/index.md

@@ -1,12 +0,0 @@
----
-okf_version: "0.1"
----
-
-# Spigot Stealth Design
-
-Spigot Stealth rewards players who spend time under invisibility effects from potions they drink, then lets unlocked players conceal their identity for a later session.
-
-## Explore
-
-- [User stories](user-stories/) - Approved requirements for progression, stealth sessions, commands, persistence, and delivery.
-- [Design log](log.md) - Material product decisions and bundle changes.

design/log.md

@@ -1,32 +0,0 @@
-# Spigot Stealth Design Log
-
-## 2026-09-05
-
-- **Completion**: Extended US-002, US-004, and US-005 with a persistent, permission-gated sleep-count policy that excludes concealed players by default, applies immediately, restores prior player state, and supports contextual administration; verified the complete Gradle build and OKF bundle.
-- **Completion**: Extended US-002 with ProtocolLib filtering of concealed sessions from multiplayer server-list counts and player samples while preserving actual online state and advertised capacity; verified the complete Gradle build and OKF bundle.
-
-## 2026-09-04
-
-- **Completion**: Extended US-002 so concealed players disconnect without a public quit announcement while ordinary quit messages remain unchanged; verified listener tests, the complete Gradle build, and the OKF bundle.
-- **Completion**: Extended US-003 and US-004 with contextual, prefix-filtered command completion that suppresses generic player suggestions, plus an administrative list of all known online and offline unlocked players; verified the complete Gradle build and OKF bundle.
-
-## 2026-08-14
-
-- **Completion**: Completed US-004 with exact known online and offline targeting, complete status, idempotent grants, confirmed resets, active concealment discovery, operator-default permissions, asynchronous persisted replies, and console audits; verified the full Gradle build.
-- **Implementation**: Began US-004 with test-first exact offline targeting, grant/reset transitions, concealed-player listing, permissions, confirmation, and audit logging.
-- **Completion**: Completed US-002 with single-use durable prepared logins, join-announcement suppression, ProtocolLib tab-only removal, scoreboard overhead-name suppression, visible physical entities, periodic observer refresh, respawn restoration, and disconnect or disable cleanup; verified the full Gradle build.
-- **Implementation**: Began US-002 with test-first prepared-login consumption, session-scoped concealment, join suppression, tab removal, and overhead-name presentation.
-- **Completion**: Completed US-003 with `/stealth progress`, live unsaved interval inclusion, configured target and remaining output, concise duration formatting, and unlocked usage guidance; verified the full Gradle build.
-- **Implementation**: Began US-003 with player-facing progress command and human-readable duration tests.
-- **Completion**: Completed US-001 with direct potion-drink effect attribution, monotonic elapsed-time accumulation, safe refresh and stop transitions, durable UUID progress, exact-once unlocking, and title plus chat presentation; verified the full Gradle build.
-- **Implementation**: Began US-001 with monotonic-clock progression tests and potion-cause event attribution.
-- **Completion**: Completed US-005 with validated eight-hour defaults and configurable messages, UUID-keyed immutable state, RFC 3339 timing metadata, safe invalid-record defaults, unknown-field preservation, atomic YAML replacement, periodic saves, and serialized off-thread persistence; verified the full Gradle build.
-- **Implementation**: Began US-005 with test-first validated settings, UUID-keyed state, and defensive asynchronous persistence.
-- **Completion**: Completed US-006 with a Java 17 Gradle build, strict compiler linting, Spigot API, JUnit 5, Mockito, plugin metadata, OKF validation, Gitea CI, conventional-commit checks, semantic releases, and versioned release assets; verified the full build and a `1.2.3` release JAR.
-- **Implementation**: Began US-006 with a test-driven Java 17, Gradle, Spigot, OKF validation, and Gitea delivery foundation modeled on Spigot Tyrant.
-- **Creation**: Established the OKF v0.1 product record for Spigot Stealth.
-- **Decision**: Only invisibility from a potion the player directly drinks contributes to the default eight-hour unlock requirement.
-- **Decision**: An unlocked player who disconnects while their qualifying potion effect remains active conceals their identity for the entirety of their next online session.
-- **Decision**: Each concealed session requires a new qualifying potion and disconnect; concealment never carries automatically into another session.
-- **Decision**: Concealed players remain physically visible but have no join announcement, tab-list entry, or overhead name tag for any player, including administrators.
-- **Decision**: Administrators can inspect and manage online or offline progression and list currently concealed players.

design/user-stories/index.md

@@ -1,8 +0,0 @@
-# Spigot Stealth User Stories
-
-1. [US-001: Accumulate invisibility time and unlock stealth](us-001-accumulate-invisibility-and-unlock.md) - Earn stealth by spending eight hours under invisibility effects from directly consumed potions.
-2. [US-002: Rejoin without a visible identity](us-002-rejoin-without-visible-identity.md) - Turn a qualifying invisible disconnect into one concealed online session.
-3. [US-003: Check personal stealth progress](us-003-check-personal-progress.md) - View accumulated time, remaining time, and unlock status.
-4. [US-004: Inspect and manage player stealth](us-004-administer-player-stealth.md) - Inspect and modify online or offline progression and find concealed players.
-5. [US-005: Configure and persist stealth progression](us-005-configure-and-persist-progression.md) - Keep progression durable and operator-configurable.
-6. [US-006: Build, test, and release the plugin](us-006-build-test-and-release.md) - Provide repeatable Gradle builds and Gitea delivery.

design/user-stories/us-001-accumulate-invisibility-and-unlock.md

@@ -1,32 +0,0 @@
----
-type: User Story
-title: "US-001: Accumulate invisibility time and unlock stealth"
-description: Reward sustained use of directly consumed invisibility potions with the stealth ability.
-status: done
----
-
-# US-001: Accumulate invisibility time and unlock stealth
-
-As a **player**, I want my qualifying invisibility time to accumulate so that sustained potion use eventually unlocks stealth.
-
-## Acceptance criteria
-
-- [x] Only time spent online under an invisibility effect produced by a potion the player directly drank contributes to progression.
-- [x] Invisibility received from splash potions, lingering potions, tipped arrows, commands, plugins, or other sources does not contribute.
-- [x] Qualifying time stops when the effect ends, is removed, is replaced by a non-qualifying source, the player disconnects, or the plugin disables.
-- [x] Refreshed or overlapping qualifying effects never count elapsed time more than once.
-- [x] Qualifying time accumulates across effects, sessions, and server restarts.
-- [x] The ability unlocks when accumulated qualifying time reaches eight hours by default.
-- [x] Reaching the threshold grants the unlock exactly once without discarding excess elapsed time.
-- [x] When an online player unlocks stealth, they receive both a full-screen title and a chat message explaining the ability.
-- [x] Progress and unlock ownership are associated with the player's UUID rather than their current name.
-
-## Validation
-
-Automated tests verify monotonic accumulation across intervals, refresh without duplicate time, exact-once threshold crossing with excess-time preservation, direct potion-drink cause filtering, non-qualifying replacement, UUID state, and online title and chat presentation. The complete `./gradlew clean check jar` lifecycle passes.
-
-## Related
-
-- [Rejoin without a visible identity](us-002-rejoin-without-visible-identity.md)
-- [Check personal stealth progress](us-003-check-personal-progress.md)
-- [Configure and persist stealth progression](us-005-configure-and-persist-progression.md)

design/user-stories/us-002-rejoin-without-visible-identity.md

@@ -1,46 +0,0 @@
----
-type: User Story
-title: "US-002: Rejoin without a visible identity"
-description: Let an unlocked player turn a qualifying invisible disconnect into one identity-concealed session.
-status: done
----
-
-# US-002: Rejoin without a visible identity
-
-As an **unlocked player**, I want to disconnect while invisibility from a potion I drank is active so that my identity is concealed throughout my next session.
-
-## Acceptance criteria
-
-- [x] An unlocked player becomes eligible for a concealed login only by disconnecting while an invisibility effect from a potion they directly drank remains active.
-- [x] A player who has not unlocked stealth cannot prepare a concealed login.
-- [x] An ordinary disconnect without an active qualifying effect clears any preparation for the next login.
-- [x] On a prepared login, no public join announcement is shown.
-- [x] When a concealed player disconnects, no public quit or disconnect announcement is shown.
-- [x] Ordinary players' quit messages remain unchanged.
-- [x] Concealment is checked before disconnect cleanup so announcement suppression is reliable.
-- [x] Throughout the concealed session, the player is absent from every other player's tab list, including administrators' tab lists.
-- [x] The multiplayer server list's online-player count excludes currently concealed players.
-- [x] Concealed players are excluded from any player-name sample shown for the server-list count, while ordinary players remain represented.
-- [x] The public count never becomes negative, and the configured maximum-player count remains unchanged.
-- [x] Server-list concealment changes only the public ping response and does not alter actual online-player state or gameplay.
-- [x] By default, concealed players are excluded from sleep-percentage calculations.
-- [x] When the sleep-count policy is `include`, concealed players count normally; ordinary players are never modified by either policy.
-- [x] A player's previous sleeping-ignore state is restored when concealment ends, the player disconnects or is reset, the policy changes to `include`, or the plugin disables.
-- [x] Policy changes apply immediately to currently concealed players.
-- [x] Throughout the concealed session, no overhead name tag identifies the player to any other player, including administrators.
-- [x] The concealed player's physical character remains visible in the world and retains ordinary movement, interaction, combat, and permission behavior.
-- [x] The concealed player receives a private message explaining that stealth is active for the session.
-- [x] Concealment lasts until the player disconnects and is handled predictably across death and plugin reload or disable events.
-- [x] Disconnecting consumes the current concealed session; another concealed login requires another qualifying potion and qualifying disconnect.
-- [x] Merely owning the unlock never conceals an ordinary login or carries concealment automatically into a later session.
-- [x] Prepared-login state survives a server restart between the qualifying disconnect and the next login.
-
-## Validation
-
-Automated tests verify unlocked and locked disconnect transitions, ordinary-disconnect clearing, one-login consumption, concealed join and quit announcement suppression, preservation of ordinary announcements, private activation messaging, ordinary-login presentation, tab removal for existing and new observers, overhead-name suppression, active concealed-session tracking, public server-list count and sample filtering, nonnegative counts, unchanged maximum capacity, default sleep-count exclusion, immediate policy changes, restoration of prior sleeping-ignore state, and the absence of entity-hiding calls. ProtocolLib is declared as a required dependency, prepared state round trips through YAML, and `./gradlew clean check jar` passes.
-
-## Related
-
-- [Accumulate invisibility time and unlock stealth](us-001-accumulate-invisibility-and-unlock.md)
-- [Inspect and manage player stealth](us-004-administer-player-stealth.md)
-- [Configure and persist stealth progression](us-005-configure-and-persist-progression.md)

design/user-stories/us-003-check-personal-progress.md

@@ -1,31 +0,0 @@
----
-type: User Story
-title: "US-003: Check personal stealth progress"
-description: Show a player their accumulated qualifying invisibility time and stealth unlock status.
-status: done
----
-
-# US-003: Check personal stealth progress
-
-As a **player**, I want to check my stealth progress so that I know how close I am to unlocking the ability and how to use it afterward.
-
-## Acceptance criteria
-
-- [x] `/stealth progress` reports the player's accumulated qualifying invisibility time.
-- [x] Before unlock, the command reports the configured target and remaining duration.
-- [x] While a qualifying effect is active, the report includes elapsed time not yet written during the current tracking interval.
-- [x] After unlock, the command clearly reports that stealth is unlocked and explains how to prepare a concealed login.
-- [x] Durations are presented in a concise, human-readable form.
-- [x] Repeated command use does not change progression or concealment state.
-- [x] The command has clear usage metadata and an appropriate player permission.
-- [x] `/stealth` tab-completes `progress`, filtered by the entered prefix.
-- [x] Unsupported argument positions return no suggestions instead of Bukkit's generic player list.
-
-## Validation
-
-Automated tests verify concise duration formatting, live in-flight progress, configured target and remaining output, command non-mutation, unlocked usage guidance, prefix-filtered completion, and suppression of irrelevant suggestions. Command metadata and the complete `./gradlew clean check jar` lifecycle pass.
-
-## Related
-
-- [Accumulate invisibility time and unlock stealth](us-001-accumulate-invisibility-and-unlock.md)
-- [Configure and persist stealth progression](us-005-configure-and-persist-progression.md)

design/user-stories/us-004-administer-player-stealth.md

@@ -1,44 +0,0 @@
----
-type: User Story
-title: "US-004: Inspect and manage player stealth"
-description: Give administrators durable controls for online and offline progression, unlocks, and active concealment.
-status: done
----
-
-# US-004: Inspect and manage player stealth
-
-As a **server administrator**, I want to inspect and correct player stealth state so that I can support players whether they are online or offline.
-
-## Acceptance criteria
-
-- [x] `/stealthadmin status <player|uuid>` reports accumulated time, unlock status, prepared-login state, and current concealment state.
-- [x] Status inspection works for online players and known offline players selected by exact current or previously recorded name or UUID.
-- [x] `/stealthadmin grant <player|uuid>` grants the unlock to an online or known offline player without altering accumulated time unnecessarily.
-- [x] Granting an already-owned unlock is safe and clearly reports that no change was needed.
-- [x] Granting the unlock sends the normal full-screen title and chat notification when the target is online.
-- [x] `/stealthadmin reset <player|uuid> confirm` clears accumulated time, unlock ownership, prepared-login state, and current concealment for an online or known offline player.
-- [x] Reset requires explicit confirmation and safely restores an online concealed player to ordinary identity presentation.
-- [x] `/stealthadmin list` lists every currently online concealed player and clearly reports when there are none.
-- [x] Concealed players remain absent from administrators' ordinary tab lists and retain hidden overhead name tags; the admin command is the supported discovery mechanism.
-- [x] Commands clearly reject unknown, ambiguous, malformed, or otherwise invalid targets without creating unintended player records.
-- [x] Administrative inspection and modification require an operator-default administrative permission.
-- [x] State-changing operations persist before success is reported and are safe under retries.
-- [x] Grant and reset actions record the administrator, target UUID, and action in the server log without blocking the server tick thread.
-- [x] `/stealthadmin` tab-completes `status`, `grant`, `reset`, and `list`, filtered by the entered prefix.
-- [x] Target positions for `status`, `grant`, and `reset` suggest known player names, and reset's final argument suggests `confirm`.
-- [x] Administrative completions require the administrative permission, and irrelevant positions return no suggestions instead of Bukkit's generic player list.
-- [x] `/stealthadmin list unlocked` lists every known online or offline player with stealth unlocked.
-- [x] The unlocked list is sorted case-insensitively, identifies nameless records by UUID, and clearly reports when it is empty.
-- [x] Existing `/stealthadmin list` behavior continues to list currently concealed online players.
-- [x] `/stealthadmin sleepcount status` reports whether concealed players are included in or excluded from sleep-percentage calculations.
-- [x] `/stealthadmin sleepcount <include|exclude>` persists the policy before reporting success, applies it immediately, and records the administrator and policy in the server log.
-- [x] The `sleepcount`, `status`, `include`, and `exclude` arguments are permission-gated and contextually tab-completed.
-
-## Validation
-
-Automated tests verify exact offline name and UUID resolution, ambiguous and unknown rejection without record creation, complete status output, idempotent grants and notification, complete resets with presentation cleanup, online concealed-player filtering, online and offline unlocked-player listing, contextual permission-gated completion, durable sleep-count status and policy changes, immediate policy refresh, confirmation and permission gates, persisted-before-success replies, and audit records. The complete `./gradlew clean check jar` lifecycle passes.
-
-## Related
-
-- [Rejoin without a visible identity](us-002-rejoin-without-visible-identity.md)
-- [Configure and persist stealth progression](us-005-configure-and-persist-progression.md)

design/user-stories/us-005-configure-and-persist-progression.md

@@ -1,36 +0,0 @@
----
-type: User Story
-title: "US-005: Configure and persist stealth progression"
-description: Give operators validated settings and durable, defensive storage for stealth behavior.
-status: done
----
-
-# US-005: Configure and persist stealth progression
-
-As a **server operator**, I want stealth progression to be configurable and durable so that the plugin remains predictable across restarts and balance changes.
-
-## Acceptance criteria
-
-- [x] The qualifying-time threshold is configurable and defaults to eight hours.
-- [x] Player-facing progress, unlock, prepared-login, and concealed-session messages are configurable.
-- [x] Startup validates required settings before registering partially functional listeners, commands, or tasks.
-- [x] Invalid required configuration prevents initialization and produces a clear server log message.
-- [x] UUID-keyed state stores accumulated qualifying duration, unlock ownership, active qualifying timing data, prepared-login state, and any current concealment metadata needed for safe recovery.
-- [x] Qualifying runtime intervals use a monotonic elapsed-time source so wall-clock adjustments cannot grant or remove progress.
-- [x] Durable timestamps, when required, use RFC 3339 UTC notation.
-- [x] State is saved periodically, after material state changes, and during orderly plugin disable.
-- [x] State uses atomic replacement where supported so an interrupted write does not replace valid data with a partial file.
-- [x] Corrupt, unknown, or invalid records cannot silently grant time, an unlock, a prepared login, or concealment.
-- [x] Unknown forward-compatible fields are preserved where practical.
-- [x] Persistence work does not perform blocking file operations on the server tick thread.
-- [x] The sleep-count policy persists in `state.yml` and defaults safely to `exclude` when missing or invalid.
-
-## Validation
-
-Verified settings defaults and rejection, packaged configuration, safe UUID-state defaults, sleep-count policy defaults and round trips, RFC 3339 round trips, unknown-field preservation, invalid-record rejection, atomic repository writes, and dedicated-thread loading and saving with automated tests and `./gradlew clean check jar`.
-
-## Related
-
-- [Accumulate invisibility time and unlock stealth](us-001-accumulate-invisibility-and-unlock.md)
-- [Rejoin without a visible identity](us-002-rejoin-without-visible-identity.md)
-- [Inspect and manage player stealth](us-004-administer-player-stealth.md)

design/user-stories/us-006-build-test-and-release.md

@@ -1,31 +0,0 @@
----
-type: User Story
-title: "US-006: Build, test, and release the plugin"
-description: Give maintainers repeatable builds, automated verification, and versioned Gitea releases.
-status: done
----
-
-# US-006: Build, test, and release the plugin
-
-As a **plugin maintainer**, I want automated builds and releases modeled on Spigot Tyrant so that tested, correctly versioned artifacts can be distributed consistently.
-
-## Acceptance criteria
-
-- [x] The Gradle Kotlin DSL project compiles against Spigot API `26.2-R0.1-SNAPSHOT` using a Java 17 toolchain.
-- [x] Compiler lint warnings fail the build.
-- [x] Automated JUnit 5 and Mockito tests run as part of the Gradle check lifecycle.
-- [x] Pushes and pull requests build and test the plugin in Gitea Actions.
-- [x] Pull requests validate conventional commit messages.
-- [x] CI stores a `spigot-stealth` development JAR as a workflow artifact.
-- [x] Main-branch conventional commits drive semantic versioning.
-- [x] A successful release builds a versioned JAR and attaches it to the corresponding Gitea release.
-- [x] Build files, Gradle wrapper, workflows, and release behavior follow `../spigot-tyrant/` where applicable while using Spigot Stealth names and identifiers.
-- [x] OKF validation using `okf-base.yaml` runs locally through the repository validation script and in CI.
-
-## Validation
-
-Verified with `./gradlew clean check jar`, a release-version `1.2.3` JAR with matching embedded plugin metadata, and `./scripts/validate-okf.sh`.
-
-## Related
-
-- [Configure and persist stealth progression](us-005-configure-and-persist-progression.md)

okf-base.yaml

@@ -1,23 +0,0 @@
-okf_version: "0.1"
-
-base:
-  name: Spigot Stealth Design
-  roots:
-    - path: design
-  reserved_files:
-    index: index.md
-    log: log.md
-
-profile:
-  types:
-    User Story:
-      required: [type, title, description, status]
-      optional: []
-      status_values: [backlog, in-progress, done]
-  date_fields: []
-
-hygiene:
-  broken_links: error
-  reserved_files: error
-  unknown_fields: error
-  split_candidates: off

scripts/validate-okf.sh

@@ -1,111 +0,0 @@
-#!/usr/bin/env bash
-# OKF Bundle Validator v0.1
-# Usage: validate.sh <bundle-path>
-# Checks conformance with OKF v0.1 spec:
-#   E1: All non-reserved .md files have YAML frontmatter
-#   E2: All frontmatter has non-empty 'type' field
-#   E3: Reserved files follow structure rules
-
-set -euo pipefail
-
-REPOSITORY_ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
-BUNDLE="${1:-${REPOSITORY_ROOT}/design}"
-MANIFEST="${REPOSITORY_ROOT}/okf-base.yaml"
-
-if command -v okflint >/dev/null 2>&1; then
-  exec okflint validate --manifest "$MANIFEST" "$BUNDLE"
-fi
-
-echo "Warning: okflint is unavailable; running core OKF v0.1 validation only." >&2
-
-ERRORS=0
-WARNINGS=0
-TOTAL=0
-
-RED='\033[0;31m'
-GREEN='\033[0;32m'
-YELLOW='\033[0;33m'
-NC='\033[0m'
-
-if [ ! -d "$BUNDLE" ]; then
-  echo -e "${RED}Error: '$BUNDLE' is not a directory${NC}"
-  exit 1
-fi
-
-echo "Validating OKF bundle: $BUNDLE"
-echo "---"
-
-# Find all .md files
-while IFS= read -r -d '' file; do
-  TOTAL=$((TOTAL + 1))
-  relative="${file#$BUNDLE/}"
-  basename=$(basename "$file")
-
-  # Skip reserved files (validate separately)
-  if [[ "$basename" == "index.md" || "$basename" == "log.md" ]]; then
-    # E3: Check reserved file structure
-    if [[ "$basename" == "index.md" ]]; then
-      # index.md should NOT have frontmatter (except bundle root may have okf_version)
-      if head -1 "$file" | grep -q "^---$"; then
-        # Allow only if it's bundle root and contains okf_version
-        if [[ "$relative" != "index.md" ]]; then
-          echo -e "${RED}E3: $relative — index.md should not have frontmatter${NC}"
-          ERRORS=$((ERRORS + 1))
-        fi
-      fi
-    fi
-    if [[ "$basename" == "log.md" ]]; then
-      # log.md should have date headings in YYYY-MM-DD format
-      if ! grep -qE "^## [0-9]{4}-[0-9]{2}-[0-9]{2}" "$file" 2>/dev/null; then
-        if [ -s "$file" ]; then
-          echo -e "${YELLOW}W: $relative — log.md has no ISO 8601 date headings${NC}"
-          WARNINGS=$((WARNINGS + 1))
-        fi
-      fi
-    fi
-    continue
-  fi
-
-  # E1: Check for YAML frontmatter
-  if ! head -1 "$file" | grep -q "^---$"; then
-    echo -e "${RED}E1: $relative — no YAML frontmatter${NC}"
-    ERRORS=$((ERRORS + 1))
-    continue
-  fi
-
-  # Extract frontmatter (between first --- and second ---)
-  frontmatter=$(sed -n '2,/^---$/p' "$file" | sed '$d')
-
-  # E2: Check for non-empty type field
-  type_value=$(echo "$frontmatter" | grep -E "^type:" | sed 's/^type:\s*//' | tr -d '"' | tr -d "'" | xargs)
-  if [ -z "$type_value" ]; then
-    echo -e "${RED}E2: $relative — missing or empty 'type' field${NC}"
-    ERRORS=$((ERRORS + 1))
-    continue
-  fi
-
-  # Warnings for recommended fields
-  if ! echo "$frontmatter" | grep -qE "^title:"; then
-    echo -e "${YELLOW}W1: $relative — missing recommended 'title' field${NC}"
-    WARNINGS=$((WARNINGS + 1))
-  fi
-  if ! echo "$frontmatter" | grep -qE "^description:"; then
-    echo -e "${YELLOW}W1: $relative — missing recommended 'description' field${NC}"
-    WARNINGS=$((WARNINGS + 1))
-  fi
-
-done < <(find "$BUNDLE" -name "*.md" -type f -print0 | sort -z)
-
-# Summary
-echo "---"
-echo "Files scanned: $TOTAL"
-if [ $ERRORS -eq 0 ]; then
-  echo -e "${GREEN}✅ Bundle is OKF v0.1 conformant${NC}"
-else
-  echo -e "${RED}❌ $ERRORS error(s) — bundle is NOT conformant${NC}"
-fi
-if [ $WARNINGS -gt 0 ]; then
-  echo -e "${YELLOW}⚠  $WARNINGS warning(s)${NC}"
-fi
-
-exit $ERRORS

settings.gradle.kts

@@ -1 +1 @@
-rootProject.name = "spigot-stealth"
+rootProject.name = "purpur-stealth"

src/main/java/games/dmg/spigotstealth/BukkitIdentityPresentation.java

@@ -18,6 +18,18 @@ public final class BukkitIdentityPresentation implements IdentityPresentation {
     private final Supplier<SleepCountPolicy> sleepCountPolicy;
     private final Map<UUID, Player> concealedPlayers = new LinkedHashMap<>();
     private final Map<UUID, Boolean> previousSleepingIgnored = new LinkedHashMap<>();
+    private final Map<UUID, String> previousDisplayNames = new LinkedHashMap<>();
+    private volatile java.util.Set<String> concealedNames = java.util.Set.of();
+
+    /** Immutable snapshot safe to read from outgoing packet threads. */
+    public java.util.Set<String> concealedNames() {
+        return concealedNames;
+    }
+
+    private void publishNames() {
+        concealedNames = concealedPlayers.values().stream().map(Player::getName)
+                .collect(java.util.stream.Collectors.toUnmodifiableSet());
+    }
 
     public BukkitIdentityPresentation(
             Supplier<? extends Collection<? extends Player>> onlinePlayers,
@@ -40,12 +52,17 @@ public final class BukkitIdentityPresentation implements IdentityPresentation {
     @Override
     public void conceal(Player player) {
         concealedPlayers.put(player.getUniqueId(), player);
+        publishNames();
+        previousDisplayNames.putIfAbsent(player.getUniqueId(), player.getDisplayName());
+        player.setDisplayName("§kAnonymous§r");
         applySleepCountPolicy(player);
         Team team = scoreboard.getTeam(teamName(player.getUniqueId()));
         if (team == null) {
             team = scoreboard.registerNewTeam(teamName(player.getUniqueId()));
         }
-        team.setOption(Team.Option.NAME_TAG_VISIBILITY, Team.OptionStatus.NEVER);
+        team.setOption(Team.Option.NAME_TAG_VISIBILITY, Team.OptionStatus.ALWAYS);
+        team.setPrefix("§k");
+        team.setSuffix("§r");
         team.addEntry(player.getName());
         for (Player observer : onlinePlayers.get()) {
             if (!observer.getUniqueId().equals(player.getUniqueId())) {
@@ -57,6 +74,10 @@ public final class BukkitIdentityPresentation implements IdentityPresentation {
     @Override
     public void reveal(Player player) {
         boolean wasConcealed = concealedPlayers.remove(player.getUniqueId()) != null;
+        publishNames();
+        if (previousDisplayNames.containsKey(player.getUniqueId())) {
+            player.setDisplayName(previousDisplayNames.remove(player.getUniqueId()));
+        }
         restoreSleepingIgnored(player);
         Team team = scoreboard.getTeam(teamName(player.getUniqueId()));
         if (team != null) {

src/main/java/games/dmg/spigotstealth/EyeCrafting.java

@@ -0,0 +1,66 @@
+package games.dmg.spigotstealth;
+
+import java.util.Objects;
+import org.bukkit.Keyed;
+import org.bukkit.Material;
+import org.bukkit.NamespacedKey;
+import org.bukkit.entity.Player;
+import org.bukkit.event.EventHandler;
+import org.bukkit.event.EventPriority;
+import org.bukkit.event.Listener;
+import org.bukkit.event.inventory.PrepareItemCraftEvent;
+import org.bukkit.inventory.ShapedRecipe;
+
+/** Personal crafting unlock for the transferable Eye. Vanilla owns ingredient consumption. */
+public final class EyeCrafting implements Listener {
+    public static final NamespacedKey RECIPE_KEY = new NamespacedKey("spigotstealth", "eye_of_true_seeing");
+    private final EyeItems items;
+    private final EyeProgressionService progression;
+
+    public EyeCrafting(EyeProgressionService progression, EyeItems items) {
+        this.progression = Objects.requireNonNull(progression, "progression");
+        this.items = Objects.requireNonNull(items, "items");
+    }
+
+    public ShapedRecipe recipe() {
+        return new ShapedRecipe(RECIPE_KEY, items.create()).shape("NNN", "NEN", "NNN")
+                .setIngredient('N', Material.NETHERITE_BLOCK).setIngredient('E', Material.ENDER_EYE);
+    }
+
+    @EventHandler(priority = EventPriority.HIGHEST, ignoreCancelled = true)
+    public void onCraft(org.bukkit.event.inventory.CraftItemEvent event) {
+        if (event.isCancelled() || !matches(event.getRecipe())) { return; }
+        if (!(event.getWhoClicked() instanceof Player player) || !progression.isUnlocked(player.getUniqueId())
+                || !accepts(event.getInventory().getMatrix()) || !items.isEye(event.getInventory().getResult())
+                || event.getInventory().getResult().getAmount() != 1) {
+            event.setCancelled(true);
+            event.getInventory().setResult(null);
+        }
+    }
+
+    @EventHandler(priority = EventPriority.HIGHEST, ignoreCancelled = true)
+    public void onCrafter(org.bukkit.event.block.CrafterCraftEvent event) {
+        if (matches(event.getRecipe())) { event.setCancelled(true); }
+    }
+
+    private static boolean matches(org.bukkit.inventory.Recipe recipe) {
+        return recipe instanceof Keyed keyed && RECIPE_KEY.equals(keyed.getKey());
+    }
+
+    private static boolean accepts(org.bukkit.inventory.ItemStack[] matrix) {
+        if (matrix.length != 9) { return false; }
+        for (int index = 0; index < matrix.length; index++) {
+            if (matrix[index] == null || matrix[index].getAmount() <= 0
+                    || matrix[index].getType() != (index == 4 ? Material.ENDER_EYE : Material.NETHERITE_BLOCK)) { return false; }
+        }
+        return true;
+    }
+
+    @EventHandler(priority = EventPriority.HIGHEST)
+    public void onPrepare(PrepareItemCraftEvent event) {
+        if (!(event.getInventory().getRecipe() instanceof Keyed keyed) || !RECIPE_KEY.equals(keyed.getKey())) { return; }
+        if (!(event.getView().getPlayer() instanceof Player player) || !progression.isUnlocked(player.getUniqueId())) {
+            event.getInventory().setResult(null);
+        }
+    }
+}

src/main/java/games/dmg/spigotstealth/EyeEquipment.java

@@ -0,0 +1,47 @@
+package games.dmg.spigotstealth;
+
+import java.util.Objects;
+import org.bukkit.entity.Player;
+import org.bukkit.event.Event;
+import org.bukkit.event.EventHandler;
+import org.bukkit.event.EventPriority;
+import org.bukkit.event.Listener;
+import org.bukkit.event.player.PlayerInteractEvent;
+import org.bukkit.inventory.EquipmentSlot;
+
+/** Player-specific eligibility and inventory movement; never invokes native Ender Eye use. */
+public final class EyeEquipment implements Listener {
+    private final EyeProgressionService progression;
+    private final EyeItems items;
+
+    public EyeEquipment(EyeProgressionService progression, EyeItems items) {
+        this.progression = Objects.requireNonNull(progression, "progression");
+        this.items = Objects.requireNonNull(items, "items");
+    }
+
+    public boolean isEligibleWearer(Player player) {
+        return progression.isUnlocked(player.getUniqueId()) && items.isEye(player.getInventory().getHelmet());
+    }
+
+    // Interact-in-air may start with block use denied; respect item-use denial rather than isCancelled().
+    @EventHandler(priority = EventPriority.HIGHEST)
+    public void onUse(PlayerInteractEvent event) {
+        if (!event.getAction().isRightClick() || event.useItemInHand() == Event.Result.DENY || !items.isEye(event.getItem())) { return; }
+        event.setUseItemInHand(Event.Result.DENY);
+        event.setUseInteractedBlock(Event.Result.DENY);
+        Player player = event.getPlayer();
+        if (player.isDead() || !progression.isUnlocked(player.getUniqueId())
+                || (event.getHand() != EquipmentSlot.HAND && event.getHand() != EquipmentSlot.OFF_HAND)) { return; }
+        var inventory = player.getInventory();
+        var helmet = inventory.getHelmet();
+        if (helmet != null && helmet.getAmount() > 0 && !helmet.getType().isAir()) { return; }
+        var held = inventory.getItem(event.getHand());
+        if (!items.isEye(held)) { return; }
+        var equipped = held.clone();
+        equipped.setAmount(1);
+        var remaining = held.clone();
+        remaining.setAmount(held.getAmount() - 1);
+        inventory.setItem(event.getHand(), remaining.getAmount() == 0 ? null : remaining);
+        inventory.setHelmet(equipped);
+    }
+}

src/main/java/games/dmg/spigotstealth/EyeItems.java

@@ -0,0 +1,34 @@
+package games.dmg.spigotstealth;
+
+import net.kyori.adventure.text.Component;
+import org.bukkit.Material;
+import org.bukkit.NamespacedKey;
+import org.bukkit.inventory.EquipmentSlot;
+import org.bukkit.inventory.ItemStack;
+import org.bukkit.persistence.PersistentDataType;
+
+/** Creates and identifies the transferable Eye; eligibility belongs to the holder's durable progression. */
+public final class EyeItems {
+    private static final NamespacedKey IDENTITY = new NamespacedKey("spigotstealth", "eye_of_true_seeing");
+
+    public ItemStack create() {
+        var eye = new ItemStack(Material.ENDER_EYE);
+        var meta = eye.getItemMeta();
+        meta.displayName(Component.text("Eye of True Seeing"));
+        meta.getPersistentDataContainer().set(IDENTITY, PersistentDataType.BYTE, (byte) 1);
+        meta.setMaxStackSize(1);
+        var equippable = meta.getEquippable();
+        equippable.setSlot(EquipmentSlot.HEAD);
+        equippable.setDispensable(false);
+        equippable.setEquipOnInteract(false);
+        equippable.setDamageOnHurt(false);
+        meta.setEquippable(equippable);
+        eye.setItemMeta(meta);
+        return eye;
+    }
+
+    public boolean isEye(ItemStack item) {
+        return item != null && item.getAmount() > 0 && item.getType() == Material.ENDER_EYE && item.hasItemMeta()
+                && Byte.valueOf((byte) 1).equals(item.getItemMeta().getPersistentDataContainer().get(IDENTITY, PersistentDataType.BYTE));
+    }
+}

src/main/java/games/dmg/spigotstealth/EyePotionListener.java

@@ -0,0 +1,101 @@
+package games.dmg.spigotstealth;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Objects;
+import java.util.UUID;
+import java.util.concurrent.CompletableFuture;
+import java.util.function.Consumer;
+import java.util.function.Function;
+import org.bukkit.entity.Player;
+import org.bukkit.event.EventHandler;
+import org.bukkit.event.EventPriority;
+import org.bukkit.event.Listener;
+import org.bukkit.event.entity.EntityPotionEffectEvent;
+import org.bukkit.event.player.PlayerQuitEvent;
+import org.bukkit.potion.PotionEffect;
+import org.bukkit.potion.PotionEffectType;
+
+/** Night Vision potion-event adapter; progression and persistence are owned by the service. */
+public final class EyePotionListener implements Listener {
+    private final EyeProgressionService progression;
+    private final Consumer<Throwable> saveFailure;
+    private final Map<UUID, PotionEffect> expectedEffects = new HashMap<>();
+
+    public EyePotionListener(EyeProgressionService progression, Consumer<Throwable> saveFailure) {
+        this.progression = Objects.requireNonNull(progression, "progression");
+        this.saveFailure = Objects.requireNonNull(saveFailure, "saveFailure");
+    }
+
+    @EventHandler(priority = EventPriority.MONITOR, ignoreCancelled = true)
+    public void onPotionEffect(EntityPotionEffectEvent event) {
+        if (event.isCancelled() || !(event.getEntity() instanceof Player player)
+                || !PotionEffectType.NIGHT_VISION.equals(event.getModifiedType())) {
+            return;
+        }
+        if (event.getAction() == EntityPotionEffectEvent.Action.CHANGED && !replacesActiveEffect(event)) {
+            return;
+        }
+        boolean addedOrChanged = event.getAction() == EntityPotionEffectEvent.Action.ADDED
+                || event.getAction() == EntityPotionEffectEvent.Action.CHANGED;
+        if (addedOrChanged && event.getCause() == EntityPotionEffectEvent.Cause.POTION_DRINK) {
+            if (!continuesEffect(expectedEffects.get(player.getUniqueId()), event.getOldEffect())) {
+                progression.abandon(player.getUniqueId());
+            }
+            expectedEffects.put(player.getUniqueId(), event.getNewEffect());
+            observe(progression.begin(player.getUniqueId()));
+        } else {
+            finish(player.getUniqueId(), event.getOldEffect());
+        }
+    }
+
+    @EventHandler(priority = EventPriority.MONITOR)
+    public void onQuit(PlayerQuitEvent event) {
+        finish(event.getPlayer().getUniqueId(), event.getPlayer().getPotionEffect(PotionEffectType.NIGHT_VISION));
+    }
+
+    /** Server-thread observation; a missing/unattributed effect cannot inherit an old drink interval. */
+    public void checkpoint(Function<UUID, Player> onlinePlayer) {
+        for (var id : progression.activePlayerIds()) {
+            Player player = onlinePlayer.apply(id);
+            var actual = player == null || !player.isOnline() || player.isDead()
+                    ? null : player.getPotionEffect(PotionEffectType.NIGHT_VISION);
+            var expected = expectedEffects.get(id);
+            if (!continuesEffect(expected, actual) || (!actual.isInfinite() && actual.getDuration() <= 0)) {
+                expectedEffects.remove(id);
+                progression.abandon(id); // Discard the unobserved tail, never attribute it to the old source.
+            } else {
+                expectedEffects.put(id, actual);
+                observe(progression.checkpoint(id));
+            }
+        }
+    }
+
+    private void finish(UUID id, PotionEffect finalEffect) {
+        var expected = expectedEffects.remove(id);
+        if (continuesEffect(expected, finalEffect)) { observe(progression.stop(id)); }
+        else { progression.abandon(id); }
+    }
+
+    private static boolean continuesEffect(PotionEffect expected, PotionEffect actual) {
+        return actual != null && expected != null && actual.getAmplifier() == expected.getAmplifier()
+                && (expected.isInfinite() ? actual.isInfinite()
+                    : !actual.isInfinite() && actual.getDuration() <= expected.getDuration());
+    }
+
+    private void observe(CompletableFuture<Void> saved) {
+        saved.whenComplete((ignored, failure) -> {
+            if (failure != null) { saveFailure.accept(failure); }
+        });
+    }
+
+    private static boolean replacesActiveEffect(EntityPotionEffectEvent event) {
+        if (!event.isOverride() || event.getOldEffect() == null || event.getNewEffect() == null) { return false; }
+        var previous = event.getOldEffect();
+        var next = event.getNewEffect();
+        // Native update can return true for particles/icons alone. Hidden weaker effects are not active yet.
+        return next.getAmplifier() > previous.getAmplifier()
+                || (next.getAmplifier() == previous.getAmplifier() && !previous.isInfinite()
+                    && (next.isInfinite() || next.getDuration() > previous.getDuration()));
+    }
+}

src/main/java/games/dmg/spigotstealth/EyeProgress.java

@@ -0,0 +1,13 @@
+package games.dmg.spigotstealth;
+
+import java.util.Map;
+
+/** Independent durable Eye of True Seeing progress. Active potion intervals are never resumed from disk. */
+public record EyeProgress(long accumulatedMillis, boolean unlocked, Map<String, Object> unknownFields) {
+    public EyeProgress {
+        if (accumulatedMillis < 0) { throw new IllegalArgumentException("Eye progress cannot be negative"); }
+        unknownFields = Map.copyOf(unknownFields);
+    }
+    public EyeProgress(long accumulatedMillis, boolean unlocked) { this(accumulatedMillis, unlocked, Map.of()); }
+    public static EyeProgress empty() { return new EyeProgress(0, false); }
+}

src/main/java/games/dmg/spigotstealth/EyeProgressionService.java

@@ -0,0 +1,73 @@
+package games.dmg.spigotstealth;
+
+import java.time.Duration;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Objects;
+import java.util.Set;
+import java.util.UUID;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.function.Consumer;
+import java.util.function.LongSupplier;
+
+/** Server-thread qualifying intervals; durable rewards are acknowledged by the existing I/O executor. */
+public final class EyeProgressionService {
+    public static final Duration UNLOCK_THRESHOLD = Duration.ofHours(8);
+    private record Interval(long startedNanos, long creditedMillis) { }
+    private final StealthStateManager states;
+    private final LongSupplier nanoTime;
+    private final Consumer<UUID> unlocked;
+    private final Map<UUID, Interval> active = new HashMap<>();
+    private final Set<UUID> announced = ConcurrentHashMap.newKeySet();
+
+    /** The notification callback must marshal Bukkit work onto the server thread. */
+    public EyeProgressionService(StealthStateManager states, LongSupplier nanoTime, Consumer<UUID> unlocked) {
+        this.states = Objects.requireNonNull(states, "states");
+        this.nanoTime = Objects.requireNonNull(nanoTime, "nanoTime");
+        this.unlocked = Objects.requireNonNull(unlocked, "unlocked");
+        states.durableSnapshot().eyes().forEach((id, progress) -> {
+            if (progress.unlocked()) { announced.add(id); }
+        });
+    }
+
+    public CompletableFuture<Void> begin(UUID id) {
+        Objects.requireNonNull(id, "id");
+        if (active.containsKey(id)) { return checkpoint(id); }
+        active.put(id, new Interval(nanoTime.getAsLong(), 0));
+        return CompletableFuture.completedFuture(null);
+    }
+
+    public CompletableFuture<Void> checkpoint(UUID id) {
+        Interval interval = active.get(id);
+        if (interval == null) { return CompletableFuture.completedFuture(null); }
+        // Keep the original start: repeated checkpoints must not discard fractional milliseconds.
+        long total = Math.max(interval.creditedMillis(), Math.max(0, nanoTime.getAsLong() - interval.startedNanos()) / 1_000_000);
+        long elapsed = total - interval.creditedMillis();
+        if (elapsed == 0) { return CompletableFuture.completedFuture(null); }
+        active.put(id, new Interval(interval.startedNanos(), total));
+        return states.update(state -> {
+            EyeProgress previous = state.eyeProgress(id);
+            long accumulated = Math.addExact(previous.accumulatedMillis(), elapsed);
+            return state.withEyeProgress(id, new EyeProgress(accumulated,
+                previous.unlocked() || accumulated >= UNLOCK_THRESHOLD.toMillis(), previous.unknownFields()));
+        }).thenRun(() -> {
+            if (isUnlocked(id) && announced.add(id)) { unlocked.accept(id); }
+        });
+    }
+
+    public CompletableFuture<Void> stop(UUID id) {
+        CompletableFuture<Void> saved = checkpoint(id);
+        active.remove(id);
+        return saved;
+    }
+
+    public CompletableFuture<Void> stopAll() {
+        return CompletableFuture.allOf(activePlayerIds().stream().map(this::stop).toArray(CompletableFuture[]::new));
+    }
+
+    /** Defensive offline sweep: do not invent credit for the unobserved interval after the last checkpoint. */
+    public void abandon(UUID id) { active.remove(id); }
+    public boolean isUnlocked(UUID id) { return states.durableSnapshot().eyeProgress(id).unlocked(); }
+    public Set<UUID> activePlayerIds() { return Set.copyOf(active.keySet()); }
+}

src/main/java/games/dmg/spigotstealth/IdentityPacketFields.java

@@ -0,0 +1,46 @@
+package games.dmg.spigotstealth;
+
+import java.lang.reflect.Constructor;
+import java.lang.reflect.Method;
+import java.lang.reflect.RecordComponent;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Optional;
+import java.util.function.UnaryOperator;
+
+/** Small reflective bridge: avoids a compile/runtime dependency on a specific NMS or Brigadier version. */
+final class IdentityPacketFields {
+    private IdentityPacketFields() { }
+
+    static List<?> filterEntries(List<?> entries, StealthChatMasker masker) throws ReflectiveOperationException {
+        List<Object> filtered = new ArrayList<>();
+        for (Object entry : entries) {
+            Method text;
+            try {
+                text = entry.getClass().getMethod("text");
+            } catch (NoSuchMethodException exception) {
+                text = entry.getClass().getMethod("getText");
+            }
+            if (!masker.isConcealedName((String) text.invoke(entry))) {
+                filtered.add(entry);
+            }
+        }
+        return List.copyOf(filtered);
+    }
+
+    static Object mapRecord(Object record, UnaryOperator<Object> mapper) throws ReflectiveOperationException {
+        RecordComponent[] components = record.getClass().getRecordComponents();
+        if (components == null) {
+            throw new IllegalArgumentException("Unsupported non-record chat binding");
+        }
+        Class<?>[] types = new Class<?>[components.length];
+        Object[] values = new Object[components.length];
+        for (int i = 0; i < components.length; i++) {
+            types[i] = components[i].getType();
+            Object value = components[i].getAccessor().invoke(record);
+            values[i] = value instanceof Optional<?> optional ? optional.map(mapper) : mapper.apply(value);
+        }
+        Constructor<?> constructor = record.getClass().getDeclaredConstructor(types);
+        return constructor.newInstance(values);
+    }
+}

src/main/java/games/dmg/spigotstealth/PersistentStealthState.java

@@ -9,11 +9,18 @@ import java.util.UUID;
 public record PersistentStealthState(
         Map<UUID, PlayerStealthState> players,
         SleepCountPolicy sleepCountPolicy,
-        Map<String, Object> unknownFields) {
+        Map<String, Object> unknownFields,
+        Map<UUID, EyeProgress> eyes) {
     public PersistentStealthState {
         players = Map.copyOf(new LinkedHashMap<>(Objects.requireNonNull(players, "players")));
         Objects.requireNonNull(sleepCountPolicy, "sleepCountPolicy");
         unknownFields = Map.copyOf(new LinkedHashMap<>(Objects.requireNonNull(unknownFields, "unknownFields")));
+        eyes = Map.copyOf(Objects.requireNonNull(eyes, "eyes"));
+    }
+
+    public PersistentStealthState(Map<UUID, PlayerStealthState> players, SleepCountPolicy sleepCountPolicy,
+            Map<String, Object> unknownFields) {
+        this(players, sleepCountPolicy, unknownFields, Map.of());
     }
 
     public PersistentStealthState(
@@ -22,6 +29,14 @@ public record PersistentStealthState(
         this(players, SleepCountPolicy.EXCLUDE, unknownFields);
     }
 
+    public EyeProgress eyeProgress(UUID playerId) { return eyes.getOrDefault(playerId, EyeProgress.empty()); }
+
+    public PersistentStealthState withEyeProgress(UUID playerId, EyeProgress progress) {
+        Map<UUID, EyeProgress> updated = new LinkedHashMap<>(eyes);
+        updated.put(playerId, progress);
+        return new PersistentStealthState(players, sleepCountPolicy, unknownFields, updated);
+    }
+
     public PlayerStealthState player(UUID playerId) {
         return players.getOrDefault(playerId, PlayerStealthState.empty(playerId));
     }
@@ -29,10 +44,10 @@ public record PersistentStealthState(
     public PersistentStealthState withPlayer(PlayerStealthState player) {
         Map<UUID, PlayerStealthState> updated = new LinkedHashMap<>(players);
         updated.put(player.playerId(), player);
-        return new PersistentStealthState(updated, sleepCountPolicy, unknownFields);
+        return new PersistentStealthState(updated, sleepCountPolicy, unknownFields, eyes);
     }
 
     public PersistentStealthState withSleepCountPolicy(SleepCountPolicy policy) {
-        return new PersistentStealthState(players, policy, unknownFields);
+        return new PersistentStealthState(players, policy, unknownFields, eyes);
     }
 }

src/main/java/games/dmg/spigotstealth/ProtocolLibIdentityMaskingListener.java

@@ -0,0 +1,136 @@
+package games.dmg.spigotstealth;
+
+import com.comphenix.protocol.PacketType;
+import com.comphenix.protocol.events.ListenerPriority;
+import com.comphenix.protocol.events.PacketAdapter;
+import com.comphenix.protocol.events.PacketContainer;
+import com.comphenix.protocol.events.PacketEvent;
+import com.comphenix.protocol.reflect.StructureModifier;
+import com.comphenix.protocol.utility.MinecraftReflection;
+import com.comphenix.protocol.wrappers.WrappedChatComponent;
+import java.util.List;
+import java.util.Objects;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.function.Consumer;
+import java.util.function.Supplier;
+import org.bukkit.plugin.Plugin;
+
+/**
+ * Outgoing identity-only masking. Registration is deliberately left to the plugin.
+ * The supplier must return an immutable, safely published snapshot (for example AtomicReference::get).
+ * It must not inspect Bukkit players or mutable session collections on the packet thread.
+ */
+public final class ProtocolLibIdentityMaskingListener extends PacketAdapter {
+    private final Supplier<Set<String>> concealedNames;
+    private final Consumer<String> warningLog;
+    private final Set<PacketType> warned = ConcurrentHashMap.newKeySet();
+
+    public ProtocolLibIdentityMaskingListener(
+            Plugin plugin, Supplier<Set<String>> concealedNames, Consumer<String> warningLog) {
+        // ProtocolLib calls the vanilla PLAYER_CHAT packet CHAT.
+        super(plugin, ListenerPriority.HIGHEST, PacketType.Play.Server.TAB_COMPLETE,
+                PacketType.Play.Server.SYSTEM_CHAT, PacketType.Play.Server.CHAT,
+                PacketType.Play.Server.DISGUISED_CHAT);
+        this.concealedNames = Objects.requireNonNull(concealedNames, "concealedNames");
+        this.warningLog = Objects.requireNonNull(warningLog, "warningLog");
+    }
+
+    @Override
+    public void onPacketSending(PacketEvent event) {
+        if (event.isCancelled()) {
+            return;
+        }
+        try {
+            Set<String> snapshot = concealedNames.get();
+            if (snapshot.isEmpty()) {
+                return;
+            }
+            StealthChatMasker masker = new StealthChatMasker(snapshot);
+            PacketContainer packet = event.getPacket().shallowClone();
+            if (event.getPacketType().equals(PacketType.Play.Server.TAB_COMPLETE)) {
+                filterSuggestions(packet, masker);
+            } else if (event.getPacketType().equals(PacketType.Play.Server.SYSTEM_CHAT)) {
+                maskSystemChat(packet, masker);
+            } else {
+                maskBoundNames(packet, masker);
+            }
+            event.setPacket(packet);
+        } catch (ReflectiveOperationException | RuntimeException exception) {
+            // Keep delivery usable; do not cancel signed chat and break the acknowledgement chain.
+            if (warned.add(event.getPacketType())) {
+                warningLog.accept("Stealth identity masking unavailable for " + event.getPacketType()
+                        + "; original packet retained. Failure: " + exception.getClass().getSimpleName());
+            }
+        }
+    }
+
+    private static void filterSuggestions(PacketContainer packet, StealthChatMasker masker)
+            throws ReflectiveOperationException {
+        StructureModifier<Object> fields = packet.getModifier();
+        for (int i = 0; i < fields.size(); i++) {
+            Object value = fields.read(i);
+            if (value instanceof List<?> entries) {
+                // Modern ClientboundCommandSuggestionsPacket stores its Entry list directly.
+                fields.write(i, IdentityPacketFields.filterEntries(entries, masker));
+                return;
+            }
+            if (value != null && value.getClass().getName().equals("com.mojang.brigadier.suggestion.Suggestions")) {
+                Object range = value.getClass().getMethod("getRange").invoke(value);
+                List<?> entries = (List<?>) value.getClass().getMethod("getList").invoke(value);
+                List<?> filtered = IdentityPacketFields.filterEntries(entries, masker);
+                fields.write(i, value.getClass().getConstructor(range.getClass(), List.class).newInstance(range, filtered));
+                return;
+            }
+        }
+        // Pre-Brigadier protocol compatibility.
+        StructureModifier<String[]> arrays = packet.getStringArrays();
+        if (arrays.size() > 0) {
+            arrays.write(0, java.util.Arrays.stream(arrays.read(0))
+                    .filter(name -> !masker.isConcealedName(name)).toArray(String[]::new));
+            return;
+        }
+        throw new IllegalStateException("Unsupported command suggestions layout");
+    }
+
+    private static void maskSystemChat(PacketContainer packet, StealthChatMasker masker) {
+        StructureModifier<WrappedChatComponent> components = packet.getChatComponents();
+        if (components.size() > 0) {
+            WrappedChatComponent original = components.read(0);
+            String json = original.getJson();
+            String masked = masker.maskAnnouncement(json);
+            if (!json.equals(masked)) {
+                components.write(0, WrappedChatComponent.fromJson(masked));
+            }
+        } else if (packet.getStrings().size() > 0) {
+            // Older SYSTEM_CHAT represents its component as JSON text.
+            String json = packet.getStrings().read(0);
+            packet.getStrings().write(0, masker.maskAnnouncement(json));
+        } else {
+            throw new IllegalStateException("Unsupported system chat layout");
+        }
+    }
+
+    private static void maskBoundNames(PacketContainer packet, StealthChatMasker masker)
+            throws ReflectiveOperationException {
+        StructureModifier<Object> fields = packet.getModifier();
+        for (int i = 0; i < fields.size(); i++) {
+            Object value = fields.read(i);
+            if (value != null && (value.getClass().getName().endsWith("ChatType$BoundNetwork")
+                    || value.getClass().getName().endsWith("ChatType$Bound"))) {
+                Object masked = IdentityPacketFields.mapRecord(value, field -> {
+                    if (field != null && MinecraftReflection.getIChatBaseComponentClass().isInstance(field)) {
+                        String json = WrappedChatComponent.fromHandle(field).getJson();
+                        String replacement = masker.maskDisplayName(json);
+                        return json.equals(replacement) ? field : WrappedChatComponent.fromJson(replacement).getHandle();
+                    }
+                    return field;
+                });
+                fields.write(i, masked);
+                return;
+            }
+        }
+        // Intentionally never touch signed body, unsigned body, UUID, signature, or filter mask.
+        throw new IllegalStateException("Unsupported player chat display-name layout");
+    }
+}

src/main/java/games/dmg/spigotstealth/ProtocolLibServerListPingListener.java

@@ -3,42 +3,35 @@ package games.dmg.spigotstealth;
 import com.comphenix.protocol.PacketType;
 import com.comphenix.protocol.events.PacketAdapter;
 import com.comphenix.protocol.events.PacketEvent;
-import com.comphenix.protocol.wrappers.WrappedGameProfile;
 import com.comphenix.protocol.wrappers.WrappedServerPing;
-import java.util.List;
 import java.util.Objects;
 import java.util.Set;
 import java.util.UUID;
+import java.util.function.Consumer;
 import java.util.function.Supplier;
 import org.bukkit.plugin.Plugin;
 
-/** Rewrites outgoing server-list responses without changing actual online-player state. */
+/** Adjusts only the count in outgoing server-list responses through ProtocolLib. */
 public final class ProtocolLibServerListPingListener extends PacketAdapter {
     private final Supplier<Set<UUID>> concealedPlayerIds;
+    private final ServerPingCompatibilityGuard compatibilityGuard;
 
-    public ProtocolLibServerListPingListener(Plugin plugin, Supplier<Set<UUID>> concealedPlayerIds) {
+    public ProtocolLibServerListPingListener(
+            Plugin plugin,
+            Supplier<Set<UUID>> concealedPlayerIds,
+            Consumer<String> warningLog) {
         super(plugin, PacketType.Status.Server.SERVER_INFO);
         this.concealedPlayerIds = Objects.requireNonNull(concealedPlayerIds, "concealedPlayerIds");
+        this.compatibilityGuard = new ServerPingCompatibilityGuard(warningLog);
     }
 
     @Override
     public void onPacketSending(PacketEvent event) {
-        WrappedServerPing visiblePing = event.getPacket().getServerPings().read(0).deepClone();
+        compatibilityGuard.run(() -> {
-        boolean sampleVisible = visiblePing.isPlayersVisible();
+            WrappedServerPing ping = event.getPacket().getServerPings().read(0);
-        List<WrappedGameProfile> sample = sampleVisible ? visiblePing.getPlayers() : List.of();
+            int visiblePlayers = ServerListPingVisibility.visibleOnlineCount(
-        Set<UUID> concealed = concealedPlayerIds.get();
+                    ping.getPlayersOnline(), concealedPlayerIds.get().size());
-        ServerListPingVisibility.Snapshot visible = ServerListPingVisibility.adjust(
+            ping.setPlayersOnline(visiblePlayers);
-                visiblePing.getPlayersOnline(),
+        });
-                visiblePing.getPlayersMaximum(),
-                sample.stream().map(WrappedGameProfile::getUUID).toList(),
-                concealed);
-        Set<UUID> visibleSampleIds = Set.copyOf(visible.samplePlayerIds());
-        visiblePing.setPlayersOnline(visible.playersOnline());
-        if (sampleVisible) {
-            visiblePing.setPlayers(sample.stream()
-                    .filter(profile -> visibleSampleIds.contains(profile.getUUID()))
-                    .toList());
-        }
-        event.getPacket().getServerPings().write(0, visiblePing);
     }
 }

src/main/java/games/dmg/spigotstealth/ServerListPingListener.java

@@ -0,0 +1,32 @@
+package games.dmg.spigotstealth;
+
+import java.util.Iterator;
+import java.util.Objects;
+import java.util.Set;
+import java.util.UUID;
+import java.util.function.Supplier;
+import org.bukkit.entity.Player;
+import org.bukkit.event.EventHandler;
+import org.bukkit.event.EventPriority;
+import org.bukkit.event.Listener;
+import org.bukkit.event.server.ServerListPingEvent;
+
+/** Filters concealed players through Bukkit's native server-list sample representation. */
+public final class ServerListPingListener implements Listener {
+    private final Supplier<Set<UUID>> concealedPlayerIds;
+
+    public ServerListPingListener(Supplier<Set<UUID>> concealedPlayerIds) {
+        this.concealedPlayerIds = Objects.requireNonNull(concealedPlayerIds, "concealedPlayerIds");
+    }
+
+    @EventHandler(priority = EventPriority.HIGHEST)
+    public void onServerListPing(ServerListPingEvent event) {
+        Set<UUID> concealed = concealedPlayerIds.get();
+        Iterator<Player> sample = event.iterator();
+        while (sample.hasNext()) {
+            if (concealed.contains(sample.next().getUniqueId())) {
+                sample.remove();
+            }
+        }
+    }
+}

src/main/java/games/dmg/spigotstealth/ServerListPingVisibility.java

@@ -20,11 +20,15 @@ public final class ServerListPingVisibility {
                 .filter(playerId -> !concealedPlayerIds.contains(playerId))
                 .toList();
         return new Snapshot(
-                Math.max(0, playersOnline - concealedPlayerIds.size()),
+                visibleOnlineCount(playersOnline, concealedPlayerIds.size()),
                 playersMaximum,
                 visibleSample);
     }
 
+    public static int visibleOnlineCount(int playersOnline, int concealedPlayers) {
+        return Math.max(0, playersOnline - concealedPlayers);
+    }
+
     public record Snapshot(int playersOnline, int playersMaximum, List<UUID> samplePlayerIds) {
         public Snapshot {
             samplePlayerIds = List.copyOf(samplePlayerIds);

src/main/java/games/dmg/spigotstealth/ServerPingCompatibilityGuard.java

@@ -0,0 +1,26 @@
+package games.dmg.spigotstealth;
+
+import java.util.Objects;
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.function.Consumer;
+
+/** Keeps an incompatible server-ping adapter from breaking responses or flooding logs. */
+public final class ServerPingCompatibilityGuard {
+    private final Consumer<String> warningLog;
+    private final AtomicBoolean warningLogged = new AtomicBoolean();
+
+    public ServerPingCompatibilityGuard(Consumer<String> warningLog) {
+        this.warningLog = Objects.requireNonNull(warningLog, "warningLog");
+    }
+
+    public void run(Runnable edit) {
+        try {
+            edit.run();
+        } catch (RuntimeException exception) {
+            if (warningLogged.compareAndSet(false, true)) {
+                warningLog.accept("Unable to adjust the public server-list player count; "
+                        + "the original response will be used: " + exception.getMessage());
+            }
+        }
+    }
+}

src/main/java/games/dmg/spigotstealth/SpigotStealthPlugin.java

@@ -12,14 +12,20 @@ import org.bukkit.plugin.java.JavaPlugin;
 /** Bukkit entry point for Spigot Stealth. */
 public final class SpigotStealthPlugin extends JavaPlugin {
     private CompletableFuture<StealthStateManager> stateManagerFuture;
+    private CompletableFuture<Void> shutdown;
+    private volatile long lifecycleEpoch;
     private StealthSettings settings;
     private QualifyingInvisibilityService progression;
     private StealthSessionService sessions;
     private IdentityPresentation identityPresentation;
     private ProtocolManager protocolManager;
+    private EyeProgressionService eyeProgression;
+    private EyePotionListener eyePotions;
+    private boolean eyeRecipeRegistered;
 
     @Override
     public void onEnable() {
+        long epoch = ++lifecycleEpoch;
         saveDefaultConfig();
         try {
             settings = StealthSettings.from(getConfig().getValues(true));
@@ -30,45 +36,73 @@ public final class SpigotStealthPlugin extends JavaPlugin {
         }
 
         Path stateFile = getDataFolder().toPath().resolve("state.yml");
-        stateManagerFuture = StealthStateManager.load(new YamlStealthStateRepository(stateFile));
+        stateManagerFuture = shutdownCompletion().thenCompose(ignored ->
+                StealthStateManager.load(new YamlStealthStateRepository(stateFile)));
         stateManagerFuture.whenComplete((manager, failure) -> {
             if (failure != null) {
                 getLogger().severe("Unable to load Spigot Stealth state: " + rootMessage(failure));
-                getServer().getScheduler().runTask(this, () -> getServer().getPluginManager().disablePlugin(this));
+                onServer(epoch, () -> getServer().getPluginManager().disablePlugin(this));
                 return;
             }
-            getServer().getScheduler().runTask(this, () -> finishInitialization(manager));
+            if (!isEnabled() || epoch != lifecycleEpoch) {
+                logSaveFailure(manager.closeAsync());
+                return;
+            }
+            try {
+                getServer().getScheduler().runTask(this, () -> {
+                    if (!isEnabled() || epoch != lifecycleEpoch) { logSaveFailure(manager.closeAsync()); }
+                    else { finishInitialization(manager, epoch); }
+                });
+            } catch (org.bukkit.plugin.IllegalPluginAccessException ignored) {
+                logSaveFailure(manager.closeAsync());
+            }
         });
     }
 
     @Override
     public void onDisable() {
-        if (protocolManager != null) {
+        ++lifecycleEpoch;
-            protocolManager.removePacketListeners(this);
+        try {
+            if (eyePotions != null) {
+                eyePotions.checkpoint(getServer()::getPlayer);
+                logSaveFailure(eyeProgression.stopAll());
             }
+            if (progression != null) { logSaveFailure(progression.stopAll()); }
+            if (protocolManager != null) { protocolManager.removePacketListeners(this); }
             if (identityPresentation != null && sessions != null) {
                 for (org.bukkit.entity.Player player : getServer().getOnlinePlayers()) {
                     if (sessions.isConcealed(player.getUniqueId())) {
-                    identityPresentation.reveal(player);
+                        try { identityPresentation.reveal(player); }
-                    sessions.endConcealment(player.getUniqueId());
+                        finally { logSaveFailure(sessions.endConcealment(player.getUniqueId())); }
                     }
                 }
             }
-        if (progression != null) {
+        } finally {
-            progression.stopAll().join();
+            try {
+                if (eyeRecipeRegistered) {
+                    getServer().removeRecipe(EyeCrafting.RECIPE_KEY);
+                    eyeRecipeRegistered = false;
                 }
-        if (stateManagerFuture != null && stateManagerFuture.isDone() && !stateManagerFuture.isCompletedExceptionally()) {
+            } finally {
-            stateManagerFuture.join().close();
+                if (stateManagerFuture != null) {
+                    shutdown = stateManagerFuture.thenCompose(StealthStateManager::closeAsync);
+                    logSaveFailure(shutdown);
                 }
             }
+        }
+    }
+
+    /** Durable shutdown acknowledgement; never wait for it on the server thread. */
+    CompletableFuture<Void> shutdownCompletion() {
+        return shutdown == null ? CompletableFuture.completedFuture(null) : shutdown;
+    }
 
     public StealthSettings settings() {
         return settings;
     }
 
-    private void finishInitialization(StealthStateManager manager) {
+    private void finishInitialization(StealthStateManager manager, long epoch) {
-        java.util.function.Consumer<Runnable> mainThread =
+        java.util.function.Consumer<Runnable> mainThread = runnable -> onServer(epoch, runnable);
-                runnable -> getServer().getScheduler().runTask(this, runnable);
         BukkitUnlockNotifier notifier = new BukkitUnlockNotifier(
                 getServer()::getPlayer,
                 mainThread,
@@ -77,17 +111,24 @@ public final class SpigotStealthPlugin extends JavaPlugin {
                 manager, settings.unlockThreshold(), System::nanoTime, notifier);
         sessions = new StealthSessionService(manager, progression);
         protocolManager = ProtocolLibrary.getProtocolManager();
-        identityPresentation = new BukkitIdentityPresentation(
+        BukkitIdentityPresentation bukkitPresentation = new BukkitIdentityPresentation(
                 getServer()::getOnlinePlayers,
                 Objects.requireNonNull(getServer().getScoreboardManager(), "scoreboard manager").getMainScoreboard(),
                 new ProtocolLibTabListController(protocolManager),
                 () -> manager.snapshot().sleepCountPolicy());
-        protocolManager.addPacketListener(
+        identityPresentation = bukkitPresentation;
-                new ProtocolLibServerListPingListener(this, sessions::concealedPlayerIds));
+        protocolManager.addPacketListener(new ProtocolLibIdentityMaskingListener(
+                this, bukkitPresentation::concealedNames, getLogger()::warning));
+        protocolManager.addPacketListener(new ProtocolLibServerListPingListener(
+                this, sessions::concealedPlayerIds, getLogger()::warning));
+        getServer().getPluginManager().registerEvents(
+                new ServerListPingListener(sessions::concealedPlayerIds), this);
         getServer().getPluginManager().registerEvents(
                 new InvisibilityEffectListener(progression, Clock.systemUTC()), this);
         getServer().getPluginManager().registerEvents(
                 new StealthSessionListener(sessions, identityPresentation, settings.concealedMessage()), this);
+        getServer().getPluginManager().registerEvents(
+                new StealthAdminJoinListener(sessions, getServer()::getOnlinePlayers), this);
         org.bukkit.command.PluginCommand stealthPluginCommand =
                 Objects.requireNonNull(getCommand("stealth"), "stealth command");
         StealthCommand stealthCommand = new StealthCommand(manager, progression, settings);
@@ -106,6 +147,36 @@ public final class SpigotStealthPlugin extends JavaPlugin {
                 settings.unlockThreshold());
         stealthAdminPluginCommand.setExecutor(stealthAdminCommand);
         stealthAdminPluginCommand.setTabCompleter(stealthAdminCommand);
+        eyeProgression = new EyeProgressionService(manager, this::monotonicNanos, id -> mainThread.accept(() -> {
+            var player = getServer().getPlayer(id);
+            if (player != null) {
+                player.discoverRecipe(EyeCrafting.RECIPE_KEY);
+                player.sendMessage("You unlocked the Eye of True Seeing! Craft it with eight Netherite Blocks around an Eye of Ender.");
+            }
+        }));
+        eyePotions = new EyePotionListener(eyeProgression,
+                failure -> getLogger().severe("Unable to save Eye progression: " + rootMessage(failure)));
+        var eyeItems = new EyeItems();
+        var eyeCrafting = new EyeCrafting(eyeProgression, eyeItems);
+        if (!getServer().addRecipe(eyeCrafting.recipe())) {
+            getLogger().severe("Unable to register the Eye recipe; disabling Stealth rather than replacing another recipe.");
+            getServer().getPluginManager().disablePlugin(this);
+            return;
+        }
+        eyeRecipeRegistered = true;
+        getServer().getPluginManager().registerEvents(eyePotions, this);
+        getServer().getPluginManager().registerEvents(eyeCrafting, this);
+        getServer().getPluginManager().registerEvents(new EyeEquipment(eyeProgression, eyeItems), this);
+        getServer().getScheduler().runTaskTimer(this, ignored -> {
+            eyePotions.checkpoint(getServer()::getPlayer);
+            for (var player : getServer().getOnlinePlayers()) {
+                if (eyeProgression.isUnlocked(player.getUniqueId())) {
+                    if (!player.hasDiscoveredRecipe(EyeCrafting.RECIPE_KEY)) { player.discoverRecipe(EyeCrafting.RECIPE_KEY); }
+                } else if (player.hasDiscoveredRecipe(EyeCrafting.RECIPE_KEY)) {
+                    player.undiscoverRecipe(EyeCrafting.RECIPE_KEY);
+                }
+            }
+        }, 20L, 20L);
         getServer().getScheduler().runTaskTimer(this, ignored -> {
             for (java.util.UUID playerId : progression.activePlayerIds()) {
                 logSaveFailure(progression.checkpoint(playerId));
@@ -120,6 +191,20 @@ public final class SpigotStealthPlugin extends JavaPlugin {
         getLogger().info("Spigot Stealth enabled");
     }
 
+    /** Clock boundary for deterministic gameplay lifecycle verification. */
+    long monotonicNanos() { return System.nanoTime(); }
+
+    private void onServer(long epoch, Runnable action) {
+        if (!isEnabled() || epoch != lifecycleEpoch) { return; }
+        try {
+            getServer().getScheduler().runTask(this, () -> {
+                if (isEnabled() && epoch == lifecycleEpoch) { action.run(); }
+            });
+        } catch (org.bukkit.plugin.IllegalPluginAccessException ignored) {
+            // A durable unlock remains saved even if disable races its notification.
+        }
+    }
+
     private void logSaveFailure(CompletableFuture<Void> save) {
         save.exceptionally(failure -> {
             getLogger().severe("Unable to save Spigot Stealth state: " + rootMessage(failure));

src/main/java/games/dmg/spigotstealth/StealthAdminJoinListener.java

@@ -0,0 +1,49 @@
+package games.dmg.spigotstealth;
+
+import java.util.Collection;
+import java.util.Objects;
+import java.util.Set;
+import java.util.UUID;
+import java.util.function.Supplier;
+import org.bukkit.entity.Player;
+import org.bukkit.event.EventHandler;
+import org.bukkit.event.EventPriority;
+import org.bukkit.event.Listener;
+import org.bukkit.event.player.PlayerJoinEvent;
+
+/** Private administrative notices after the HIGHEST-priority session transition. */
+public final class StealthAdminJoinListener implements Listener {
+    private static final String PERMISSION = "spigotstealth.admin";
+    private static final String HINT = " Use /stealthadmin list to see who.";
+    private final StealthSessionService sessions;
+    private final Supplier<? extends Collection<? extends Player>> onlinePlayers;
+
+    public StealthAdminJoinListener(
+            StealthSessionService sessions,
+            Supplier<? extends Collection<? extends Player>> onlinePlayers) {
+        this.sessions = Objects.requireNonNull(sessions, "sessions");
+        this.onlinePlayers = Objects.requireNonNull(onlinePlayers, "onlinePlayers");
+    }
+
+    @EventHandler(priority = EventPriority.MONITOR)
+    public void onJoin(PlayerJoinEvent event) {
+        Player joining = event.getPlayer();
+        Set<UUID> concealed = sessions.concealedPlayerIds();
+        int count = concealed.size();
+        if (count == 0) {
+            return;
+        }
+        String quantity = count + (count == 1 ? " player is" : " players are");
+        if (joining.hasPermission(PERMISSION)) {
+            joining.sendMessage("[Stealth] " + quantity + " invisible." + HINT);
+        }
+        if (concealed.contains(joining.getUniqueId())) {
+            String notice = "[Stealth] An invisible player joined. " + quantity + " now invisible." + HINT;
+            for (Player observer : onlinePlayers.get()) {
+                if (!observer.getUniqueId().equals(joining.getUniqueId()) && observer.hasPermission(PERMISSION)) {
+                    observer.sendMessage(notice);
+                }
+            }
+        }
+    }
+}

src/main/java/games/dmg/spigotstealth/StealthChatMasker.java

@@ -0,0 +1,117 @@
+package games.dmg.spigotstealth;
+
+import com.google.gson.JsonArray;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonParseException;
+import com.google.gson.JsonParser;
+import java.util.Locale;
+import java.util.Set;
+import java.util.stream.Collectors;
+
+/** Masks semantic name slots, never searching/replacing user-authored message text. */
+public final class StealthChatMasker {
+    private static final Set<String> NAME_FIRST_TRANSLATIONS = Set.of(
+            "chat.type.text", "chat.type.announcement", "chat.type.emote",
+            "commands.message.display.incoming", "commands.message.display.outgoing",
+            "chat.type.advancement.task", "chat.type.advancement.goal", "chat.type.advancement.challenge");
+    private final Set<String> names;
+
+    public StealthChatMasker(Set<String> concealedNames) {
+        names = concealedNames.stream().map(name -> name.toLowerCase(Locale.ROOT)).collect(Collectors.toUnmodifiableSet());
+    }
+
+    public boolean isConcealedName(String text) {
+        return names.contains(text.toLowerCase(Locale.ROOT));
+    }
+
+    public String maskAnnouncement(String json) {
+        try {
+            JsonElement component = JsonParser.parseString(json);
+            return maskAnnouncement(component) ? component.toString() : json;
+        } catch (JsonParseException | IllegalStateException exception) {
+            return json;
+        }
+    }
+
+    public String maskDisplayName(String json) {
+        try {
+            return isConcealedName(plainName(JsonParser.parseString(json))) ? anonymous().toString() : json;
+        } catch (JsonParseException | IllegalStateException exception) {
+            return json;
+        }
+    }
+
+    private boolean maskAnnouncement(JsonElement component) {
+        boolean changed = false;
+        if (component.isJsonArray()) {
+            for (JsonElement child : component.getAsJsonArray()) {
+                changed |= maskAnnouncement(child);
+            }
+            if (changed && !component.getAsJsonArray().isEmpty()) {
+                clearInheritedActions(component.getAsJsonArray().get(0));
+            }
+        } else if (component.isJsonObject()) {
+            JsonObject object = component.getAsJsonObject();
+            // Translation arguments other than the explicitly known name slot are message content.
+            if (object.has("translate") && object.get("translate").isJsonPrimitive()
+                    && NAME_FIRST_TRANSLATIONS.contains(object.get("translate").getAsString())
+                    && object.has("with") && object.get("with").isJsonArray()) {
+                JsonArray arguments = object.getAsJsonArray("with");
+                if (!arguments.isEmpty() && isConcealedName(plainName(arguments.get(0)))) {
+                    arguments.set(0, anonymous());
+                    changed = true;
+                }
+            }
+            if (object.has("extra")) {
+                changed |= maskAnnouncement(object.get("extra"));
+            }
+            // Prevent masked descendants from inheriting an identifying action from their parent.
+            if (changed) {
+                clearInheritedActions(object);
+            }
+        }
+        return changed;
+    }
+
+    private static void clearInheritedActions(JsonElement component) {
+        if (component.isJsonObject()) {
+            for (String key : Set.of("hoverEvent", "clickEvent", "hover_event", "click_event", "insertion")) {
+                component.getAsJsonObject().remove(key);
+            }
+        } else if (component.isJsonArray() && !component.getAsJsonArray().isEmpty()) {
+            clearInheritedActions(component.getAsJsonArray().get(0));
+        }
+    }
+
+    private static String plainName(JsonElement component) {
+        if (component.isJsonPrimitive()) {
+            return component.getAsString();
+        }
+        StringBuilder text = new StringBuilder();
+        if (component.isJsonArray()) {
+            for (JsonElement child : component.getAsJsonArray()) {
+                text.append(plainName(child));
+            }
+        } else if (component.isJsonObject()) {
+            JsonObject object = component.getAsJsonObject();
+            if (object.has("text") && object.get("text").isJsonPrimitive()) {
+                text.append(object.get("text").getAsString());
+            }
+            if (object.has("extra")) {
+                text.append(plainName(object.get("extra")));
+            }
+        }
+        return text.toString();
+    }
+
+    private static JsonObject anonymous() {
+        JsonObject alias = new JsonObject();
+        alias.addProperty("text", "Anonymous");
+        alias.addProperty("obfuscated", true);
+        alias.add("hoverEvent", com.google.gson.JsonNull.INSTANCE);
+        alias.add("clickEvent", com.google.gson.JsonNull.INSTANCE);
+        alias.addProperty("insertion", "");
+        return alias;
+    }
+}

src/main/java/games/dmg/spigotstealth/StealthStateManager.java

@@ -14,7 +14,9 @@ import java.util.function.UnaryOperator;
 public final class StealthStateManager implements AutoCloseable {
     private final StealthStateRepository repository;
     private final AtomicReference<PersistentStealthState> state;
+    private final AtomicReference<PersistentStealthState> durableState;
     private final ExecutorService ioExecutor;
+    private CompletableFuture<Void> closing;
 
     public StealthStateManager(StealthStateRepository repository, PersistentStealthState initialState) {
         this(repository, initialState, newIoExecutor());
@@ -26,6 +28,7 @@ public final class StealthStateManager implements AutoCloseable {
             ExecutorService ioExecutor) {
         this.repository = Objects.requireNonNull(repository, "repository");
         this.state = new AtomicReference<>(Objects.requireNonNull(initialState, "initialState"));
+        this.durableState = new AtomicReference<>(initialState);
         this.ioExecutor = ioExecutor;
     }
 
@@ -35,7 +38,7 @@ public final class StealthStateManager implements AutoCloseable {
         return CompletableFuture.supplyAsync(() -> {
             try {
                 return new StealthStateManager(repository, repository.load(), executor);
-            } catch (IOException exception) {
+            } catch (IOException | RuntimeException exception) {
                 executor.shutdown();
                 throw new CompletionException(exception);
             }
@@ -46,38 +49,53 @@ public final class StealthStateManager implements AutoCloseable {
         return state.get();
     }
 
-    public CompletableFuture<Void> update(UnaryOperator<PersistentStealthState> operation) {
+    /** Last successfully written snapshot, for rewards that must not precede persistence acknowledgement. */
+    public PersistentStealthState durableSnapshot() { return durableState.get(); }
+
+    public synchronized CompletableFuture<Void> update(UnaryOperator<PersistentStealthState> operation) {
+        if (closing != null) { return CompletableFuture.failedFuture(new IllegalStateException("Stealth state is closing")); }
         PersistentStealthState updated = state.updateAndGet(operation);
         return persist(updated);
     }
 
-    public CompletableFuture<Void> save() {
+    public synchronized CompletableFuture<Void> save() {
-        return persist(state.get());
+        return closing == null ? persist(state.get()) : closing;
     }
 
     private CompletableFuture<Void> persist(PersistentStealthState snapshot) {
         return CompletableFuture.runAsync(() -> {
             try {
                 repository.save(snapshot);
+                durableState.set(snapshot);
             } catch (IOException exception) {
                 throw new CompletionException(exception);
             }
         }, ioExecutor);
     }
 
+    /** Queue the final snapshot and stop accepting mutations, without waiting on the caller's thread. */
+    public synchronized CompletableFuture<Void> closeAsync() {
+        if (closing == null) {
+            closing = persist(state.get());
+            ioExecutor.shutdown();
+        }
+        return closing;
+    }
+
+    /** Blocking convenience for non-server callers such as tests; server lifecycle callers should use closeAsync. */
     @Override
     public void close() {
-        save().join();
-        ioExecutor.shutdown();
         try {
-            if (!ioExecutor.awaitTermination(10L, TimeUnit.SECONDS)) {
+            closeAsync().join();
-                ioExecutor.shutdownNow();
+        } finally {
-            }
+            try {
+                if (!ioExecutor.awaitTermination(10L, TimeUnit.SECONDS)) { ioExecutor.shutdownNow(); }
             } catch (InterruptedException exception) {
                 ioExecutor.shutdownNow();
                 Thread.currentThread().interrupt();
             }
         }
+    }
 
     private static ExecutorService newIoExecutor() {
         return Executors.newSingleThreadExecutor(runnable -> {

src/main/java/games/dmg/spigotstealth/YamlStealthStateRepository.java

@@ -17,7 +17,8 @@ import org.bukkit.configuration.file.YamlConfiguration;
 
 /** Defensive YAML repository using atomic file replacement where available. */
 public final class YamlStealthStateRepository implements StealthStateRepository {
-    private static final Set<String> ROOT_FIELDS = Set.of("schema-version", "sleep-count-policy", "players");
+    private static final Set<String> ROOT_FIELDS = Set.of("schema-version", "sleep-count-policy", "players", "eye-progress");
+    private static final Set<String> EYE_FIELDS = Set.of("accumulated-millis", "unlocked");
     private static final Set<String> PLAYER_FIELDS = Set.of(
             "last-known-name", "accumulated-millis", "unlocked", "prepared-login", "concealed", "qualifying-since");
     private final Path stateFile;
@@ -56,14 +57,15 @@ public final class YamlStealthStateRepository implements StealthStateRepository
         return new PersistentStealthState(
                 players,
                 SleepCountPolicy.fromPersisted(yaml.get("sleep-count-policy")),
-                unknownRoot);
+                unknownRoot,
+                parseEyes(yaml.getConfigurationSection("eye-progress")));
     }
 
     @Override
     public void save(PersistentStealthState state) throws IOException {
         YamlConfiguration yaml = new YamlConfiguration();
         state.unknownFields().forEach(yaml::set);
-        yaml.set("schema-version", 1);
+        yaml.set("schema-version", 2);
         yaml.set("sleep-count-policy", state.sleepCountPolicy().persistedValue());
         for (PlayerStealthState player : state.players().values()) {
             String base = "players." + player.playerId() + ".";
@@ -75,6 +77,12 @@ public final class YamlStealthStateRepository implements StealthStateRepository
             yaml.set(base + "concealed", player.concealed());
             yaml.set(base + "qualifying-since", player.qualifyingSince() == null ? null : player.qualifyingSince().toString());
         }
+        state.eyes().forEach((id, progress) -> {
+            String base = "eye-progress." + id + ".";
+            progress.unknownFields().forEach((key, value) -> yaml.set(base + key, value));
+            yaml.set(base + "accumulated-millis", progress.accumulatedMillis());
+            yaml.set(base + "unlocked", progress.unlocked());
+        });
         Path parent = stateFile.toAbsolutePath().getParent();
         if (parent != null) {
             Files.createDirectories(parent);
@@ -88,6 +96,27 @@ public final class YamlStealthStateRepository implements StealthStateRepository
         }
     }
 
+    private static Map<UUID, EyeProgress> parseEyes(ConfigurationSection section) {
+        Map<UUID, EyeProgress> eyes = new LinkedHashMap<>();
+        if (section == null) { return eyes; }
+        for (String key : section.getKeys(false)) {
+            try {
+                UUID id = UUID.fromString(key);
+                ConfigurationSection entry = section.getConfigurationSection(key);
+                if (entry == null) { continue; }
+                Object raw = entry.get("accumulated-millis");
+                if (!(raw instanceof Long || raw instanceof Integer || raw instanceof Short || raw instanceof Byte)) {
+                    continue;
+                }
+                eyes.put(id, new EyeProgress(requireNonNegativeLong(entry, "accumulated-millis"),
+                    requireBoolean(entry, "unlocked"), unknownValues(entry, EYE_FIELDS)));
+            } catch (IllegalArgumentException ignored) {
+                // A malformed Eye record cannot grant an unlock or erase independent Stealth records.
+            }
+        }
+        return eyes;
+    }
+
     private static PlayerStealthState parsePlayer(UUID playerId, ConfigurationSection section) {
         long accumulated = requireNonNegativeLong(section, "accumulated-millis");
         boolean unlocked = requireBoolean(section, "unlocked");

src/nativeTest/java/games/dmg/spigotstealth/EyeCraftingTest.java

@@ -0,0 +1,215 @@
+package games.dmg.spigotstealth;
+
+import static org.junit.jupiter.api.Assertions.*;
+import static org.mockito.Mockito.*;
+
+import java.nio.file.Path;
+import java.util.UUID;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicReference;
+import org.bukkit.Material;
+import org.bukkit.entity.Player;
+import org.bukkit.event.inventory.PrepareItemCraftEvent;
+import org.bukkit.inventory.CraftingInventory;
+import org.bukkit.inventory.InventoryView;
+import org.bukkit.inventory.ItemStack;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+
+class EyeCraftingTest {
+    @TempDir Path directory;
+    @BeforeAll static void bootstrap() throws Exception { NativeRuntime.bootstrap(); }
+
+    @Test
+    void eightNetheriteBlocksAroundAnEnderEyeCanOnlyBeCraftedAfterThePersonalUnlock() throws Exception {
+        var repository = new YamlStealthStateRepository(directory.resolve("state.yml"));
+        UUID id = UUID.randomUUID();
+        try (var states = new StealthStateManager(repository, repository.load())) {
+            var progression = new EyeProgressionService(states, () -> 0L, ignored -> { });
+            var items = new EyeItems();
+            var crafting = new EyeCrafting(progression, items);
+            var recipe = crafting.recipe();
+            assertArrayEquals(new String[] {"NNN", "NEN", "NNN"}, recipe.getShape());
+            assertEquals(Material.NETHERITE_BLOCK, recipe.getIngredientMap().get('N').getType());
+            assertEquals(Material.ENDER_EYE, recipe.getIngredientMap().get('E').getType());
+            assertTrue(items.isEye(recipe.getResult()));
+            var player = mock(Player.class);
+            when(player.getUniqueId()).thenReturn(id);
+            var inventory = mock(CraftingInventory.class);
+            when(inventory.getRecipe()).thenReturn(recipe);
+            when(inventory.getMatrix()).thenReturn(matrix());
+            var result = new AtomicReference<>(recipe.getResult());
+            when(inventory.getResult()).thenAnswer(ignored -> result.get());
+            doAnswer(call -> { result.set(call.getArgument(0)); return null; }).when(inventory).setResult(any());
+            var view = mock(InventoryView.class);
+            when(view.getPlayer()).thenReturn(player);
+            when(view.getTopInventory()).thenReturn(inventory);
+            var event = new PrepareItemCraftEvent(inventory, view, false);
+            crafting.onPrepare(event);
+            assertNull(result.get(), "a locked player cannot obtain the recipe result");
+            states.update(state -> state.withEyeProgress(id, new EyeProgress(28_800_000, true))).get(3, TimeUnit.SECONDS);
+            result.set(recipe.getResult()); // A fresh native recipe preparation after earning the unlock.
+            crafting.onPrepare(event);
+            assertTrue(items.isEye(result.get()));
+            assertEquals(1, result.get().getAmount());
+            verify(inventory, never()).setMatrix(any()); // Vanilla owns all ingredient consumption.
+        }
+    }
+
+    @Test
+    void resultClicksRecheckEligibilityIngredientsAndIdentityWithoutBypassingCancellation() throws Exception {
+        var repository = new YamlStealthStateRepository(directory.resolve("state.yml"));
+        UUID id = UUID.randomUUID();
+        try (var states = new StealthStateManager(repository, repository.load())) {
+            var progression = new EyeProgressionService(states, () -> 0L, ignored -> { });
+            var items = new EyeItems();
+            var crafting = new EyeCrafting(progression, items);
+            var recipe = crafting.recipe();
+            var player = mock(Player.class);
+            when(player.getUniqueId()).thenReturn(id);
+            var inventory = mock(CraftingInventory.class);
+            when(inventory.getRecipe()).thenReturn(recipe);
+            ItemStack[] ingredients = matrix();
+            when(inventory.getMatrix()).thenReturn(ingredients);
+            var result = new AtomicReference<>(recipe.getResult());
+            when(inventory.getResult()).thenAnswer(ignored -> result.get());
+            doAnswer(call -> { result.set(call.getArgument(0)); return null; }).when(inventory).setResult(any());
+            var view = mock(InventoryView.class);
+            when(view.getPlayer()).thenReturn(player);
+            when(view.getTopInventory()).thenReturn(inventory);
+            var locked = click(recipe, view);
+            crafting.onCraft(locked);
+            assertTrue(locked.isCancelled(), "a stale preview must not bypass the personal unlock on shift-click");
+            assertNull(result.get());
+            states.update(state -> state.withEyeProgress(id, new EyeProgress(28_800_000, true))).get(3, TimeUnit.SECONDS);
+            result.set(recipe.getResult());
+            var allowed = click(recipe, view);
+            crafting.onCraft(allowed);
+            assertFalse(allowed.isCancelled());
+            assertTrue(items.isEye(result.get()));
+            ingredients[0] = new ItemStack(Material.DIRT);
+            var invalidIngredients = click(recipe, view);
+            crafting.onCraft(invalidIngredients);
+            assertTrue(invalidIngredients.isCancelled());
+            assertNull(result.get());
+            ingredients[0] = new ItemStack(Material.NETHERITE_BLOCK);
+            result.set(new ItemStack(Material.ENDER_EYE));
+            var invalidResult = click(recipe, view);
+            crafting.onCraft(invalidResult);
+            assertTrue(invalidResult.isCancelled());
+            result.set(recipe.getResult());
+            result.get().setAmount(2);
+            var inflatedResult = click(recipe, view);
+            crafting.onCraft(inflatedResult);
+            assertTrue(inflatedResult.isCancelled());
+            result.set(recipe.getResult());
+            var cancelled = click(recipe, view);
+            cancelled.setCancelled(true);
+            crafting.onCraft(cancelled);
+            assertTrue(cancelled.isCancelled());
+            var otherRecipe = new org.bukkit.inventory.ShapedRecipe(new org.bukkit.NamespacedKey("other", "eye"),
+                    new ItemStack(Material.ENDER_EYE)).shape("E").setIngredient('E', Material.ENDER_EYE);
+            var unrelated = click(otherRecipe, view);
+            crafting.onCraft(unrelated);
+            assertFalse(unrelated.isCancelled());
+            verify(inventory, never()).setMatrix(any());
+        }
+    }
+
+    @Test
+    void pendingOrFailedUnlockWritesCannotExposeACraftableResult() throws Exception {
+        var disk = new YamlStealthStateRepository(directory.resolve("state.yml"));
+        var started = new java.util.concurrent.CountDownLatch(1);
+        var release = new java.util.concurrent.CountDownLatch(1);
+        var firstWrite = new java.util.concurrent.atomic.AtomicBoolean(true);
+        StealthStateRepository repository = new StealthStateRepository() {
+            @Override public PersistentStealthState load() throws java.io.IOException { return disk.load(); }
+            @Override public void save(PersistentStealthState state) throws java.io.IOException {
+                if (firstWrite.getAndSet(false)) {
+                    started.countDown();
+                    try {
+                        if (!release.await(3, TimeUnit.SECONDS)) { throw new java.io.IOException("Test write gate timed out"); }
+                    } catch (InterruptedException exception) {
+                        Thread.currentThread().interrupt();
+                        throw new java.io.IOException(exception);
+                    }
+                    throw new java.io.IOException("Injected write failure");
+                }
+                disk.save(state);
+            }
+        };
+        UUID id = UUID.randomUUID();
+        try (var states = new StealthStateManager(repository, repository.load())) {
+            try {
+                var items = new EyeItems();
+                var crafting = new EyeCrafting(new EyeProgressionService(states, () -> 0L, ignored -> { }), items);
+                var recipe = crafting.recipe();
+                var player = mock(Player.class);
+                when(player.getUniqueId()).thenReturn(id);
+                var inventory = mock(CraftingInventory.class);
+                when(inventory.getRecipe()).thenReturn(recipe);
+                when(inventory.getMatrix()).thenReturn(matrix());
+                var result = new AtomicReference<>(recipe.getResult());
+                when(inventory.getResult()).thenAnswer(ignored -> result.get());
+                doAnswer(call -> { result.set(call.getArgument(0)); return null; }).when(inventory).setResult(any());
+                var view = mock(InventoryView.class);
+                when(view.getPlayer()).thenReturn(player);
+                when(view.getTopInventory()).thenReturn(inventory);
+                var event = new PrepareItemCraftEvent(inventory, view, false);
+                var pending = states.update(state -> state.withEyeProgress(id, new EyeProgress(28_800_000, true)));
+                assertTrue(started.await(3, TimeUnit.SECONDS));
+                assertTrue(states.snapshot().eyeProgress(id).unlocked());
+                crafting.onPrepare(event);
+                assertNull(result.get(), "in-memory progress is not a durable crafting unlock");
+                release.countDown();
+                assertThrows(java.util.concurrent.ExecutionException.class, () -> pending.get(3, TimeUnit.SECONDS));
+                result.set(recipe.getResult());
+                crafting.onPrepare(event);
+                assertNull(result.get(), "failed writes must not grant the recipe");
+                var denied = click(recipe, view);
+                crafting.onCraft(denied);
+                assertTrue(denied.isCancelled());
+                states.save().get(3, TimeUnit.SECONDS);
+                result.set(recipe.getResult());
+                crafting.onPrepare(event);
+                assertTrue(items.isEye(result.get()));
+                var allowed = click(recipe, view);
+                crafting.onCraft(allowed);
+                assertFalse(allowed.isCancelled());
+            } finally { release.countDown(); }
+        }
+    }
+
+    @Test
+    void automatedCraftersCannotBypassPersonalProgression() throws Exception {
+        var repository = new YamlStealthStateRepository(directory.resolve("state.yml"));
+        try (var states = new StealthStateManager(repository, repository.load())) {
+            var items = new EyeItems();
+            var crafting = new EyeCrafting(new EyeProgressionService(states, () -> 0L, ignored -> { }), items);
+            var block = mock(org.bukkit.block.Block.class);
+            var event = new org.bukkit.event.block.CrafterCraftEvent(block, crafting.recipe(), items.create());
+            crafting.onCrafter(event);
+            assertTrue(event.isCancelled(), "a block has no personal Eye unlock");
+            var other = new org.bukkit.inventory.ShapedRecipe(new org.bukkit.NamespacedKey("other", "eye"),
+                    new ItemStack(Material.ENDER_EYE)).shape("E").setIngredient('E', Material.ENDER_EYE);
+            var unrelated = new org.bukkit.event.block.CrafterCraftEvent(block, other, other.getResult());
+            crafting.onCrafter(unrelated);
+            assertFalse(unrelated.isCancelled());
+        }
+    }
+
+    private static org.bukkit.event.inventory.CraftItemEvent click(org.bukkit.inventory.Recipe recipe, InventoryView view) {
+        return new org.bukkit.event.inventory.CraftItemEvent(recipe, view,
+                org.bukkit.event.inventory.InventoryType.SlotType.RESULT, 0,
+                org.bukkit.event.inventory.ClickType.SHIFT_LEFT, org.bukkit.event.inventory.InventoryAction.MOVE_TO_OTHER_INVENTORY);
+    }
+
+    private static ItemStack[] matrix() {
+        var result = new ItemStack[9];
+        for (int index = 0; index < result.length; index++) {
+            result[index] = new ItemStack(index == 4 ? Material.ENDER_EYE : Material.NETHERITE_BLOCK);
+        }
+        return result;
+    }
+}

src/nativeTest/java/games/dmg/spigotstealth/EyeEquipmentTest.java

@@ -0,0 +1,92 @@
+package games.dmg.spigotstealth;
+
+import static org.junit.jupiter.api.Assertions.*;
+import static org.mockito.Mockito.*;
+
+import java.nio.file.Path;
+import java.util.EnumMap;
+import java.util.UUID;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicReference;
+import org.bukkit.Material;
+import org.bukkit.block.BlockFace;
+import org.bukkit.entity.Player;
+import org.bukkit.event.Event;
+import org.bukkit.event.block.Action;
+import org.bukkit.event.player.PlayerInteractEvent;
+import org.bukkit.inventory.EquipmentSlot;
+import org.bukkit.inventory.ItemStack;
+import org.bukkit.inventory.PlayerInventory;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+
+class EyeEquipmentTest {
+    @TempDir Path directory;
+    @BeforeAll static void bootstrap() throws Exception { NativeRuntime.bootstrap(); }
+
+    @Test
+    void tradedEyesRequireTheHoldersOwnUnlockAndEquipWithoutThrowingOrReplacingAHelmet() throws Exception {
+        UUID earner = UUID.randomUUID(), holder = UUID.randomUUID();
+        var repository = new YamlStealthStateRepository(directory.resolve("state.yml"));
+        try (var states = new StealthStateManager(repository, repository.load())) {
+            states.update(state -> state.withEyeProgress(earner, new EyeProgress(28_800_000, true))).get(3, TimeUnit.SECONDS);
+            var items = new EyeItems();
+            var equipment = new EyeEquipment(new EyeProgressionService(states, () -> 0L, ignored -> { }), items);
+            var player = mock(Player.class);
+            when(player.getUniqueId()).thenReturn(holder);
+            var inventory = mock(PlayerInventory.class);
+            when(player.getInventory()).thenReturn(inventory);
+            var helmet = new AtomicReference<ItemStack>();
+            when(inventory.getHelmet()).thenAnswer(ignored -> helmet.get());
+            doAnswer(call -> { helmet.set(call.getArgument(0)); return null; }).when(inventory).setHelmet(any());
+            var hands = new EnumMap<EquipmentSlot, ItemStack>(EquipmentSlot.class);
+            when(inventory.getItem(any(EquipmentSlot.class))).thenAnswer(call -> hands.get(call.getArgument(0)));
+            doAnswer(call -> { hands.put(call.getArgument(0), call.getArgument(1)); return null; })
+                    .when(inventory).setItem(any(EquipmentSlot.class), nullable(ItemStack.class));
+            ItemStack traded = items.create();
+            hands.put(EquipmentSlot.HAND, traded);
+            helmet.set(traded.clone());
+            assertFalse(equipment.isEligibleWearer(player), "equipping somebody else's Eye must not bypass the personal unlock");
+            helmet.set(null);
+            var denied = use(player, traded, EquipmentSlot.HAND);
+            equipment.onUse(denied);
+            assertEquals(Event.Result.DENY, denied.useItemInHand(), "custom Eyes must never fall through to vanilla Ender Eye use");
+            assertNull(helmet.get());
+            assertSame(traded, hands.get(EquipmentSlot.HAND));
+            states.update(state -> state.withEyeProgress(holder, new EyeProgress(28_800_000, true))).get(3, TimeUnit.SECONDS);
+            var allowed = use(player, traded, EquipmentSlot.HAND);
+            equipment.onUse(allowed);
+            assertEquals(Event.Result.DENY, allowed.useItemInHand());
+            assertNull(hands.get(EquipmentSlot.HAND));
+            assertTrue(items.isEye(helmet.get()));
+            assertEquals(1, helmet.get().getAmount());
+            assertTrue(equipment.isEligibleWearer(player));
+            var ordinaryHelmet = new ItemStack(Material.IRON_HELMET);
+            helmet.set(ordinaryHelmet);
+            hands.put(EquipmentSlot.OFF_HAND, items.create());
+            equipment.onUse(use(player, hands.get(EquipmentSlot.OFF_HAND), EquipmentSlot.OFF_HAND));
+            assertSame(ordinaryHelmet, helmet.get());
+            assertTrue(items.isEye(hands.get(EquipmentSlot.OFF_HAND)));
+            assertFalse(equipment.isEligibleWearer(player), "holding an Eye is not wearing it");
+            helmet.set(null);
+            equipment.onUse(use(player, hands.get(EquipmentSlot.OFF_HAND), EquipmentSlot.OFF_HAND));
+            assertNull(hands.get(EquipmentSlot.OFF_HAND));
+            assertTrue(equipment.isEligibleWearer(player));
+            helmet.set(null);
+            hands.put(EquipmentSlot.HAND, items.create());
+            var cancelled = use(player, hands.get(EquipmentSlot.HAND), EquipmentSlot.HAND);
+            cancelled.setUseItemInHand(Event.Result.DENY);
+            equipment.onUse(cancelled);
+            assertNull(helmet.get());
+            assertTrue(items.isEye(hands.get(EquipmentSlot.HAND)));
+            var ordinary = use(player, new ItemStack(Material.ENDER_EYE), EquipmentSlot.HAND);
+            equipment.onUse(ordinary);
+            assertEquals(Event.Result.DEFAULT, ordinary.useItemInHand());
+        }
+    }
+
+    private static PlayerInteractEvent use(Player player, ItemStack item, EquipmentSlot hand) {
+        return new PlayerInteractEvent(player, Action.RIGHT_CLICK_AIR, item, null, BlockFace.SELF, hand);
+    }
+}

src/nativeTest/java/games/dmg/spigotstealth/EyeItemsTest.java

@@ -0,0 +1,39 @@
+package games.dmg.spigotstealth;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import net.kyori.adventure.text.Component;
+import org.bukkit.Material;
+import org.bukkit.inventory.EquipmentSlot;
+import org.bukkit.inventory.ItemStack;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+
+class EyeItemsTest {
+    @BeforeAll static void bootstrap() throws Exception { NativeRuntime.bootstrap(); }
+
+    @Test
+    void createdEyeIsAnAuthenticatedHelmetItemButPlainAndRenamedEyesAreNot() {
+        var items = new EyeItems();
+        ItemStack eye = items.create();
+        assertEquals(Material.ENDER_EYE, eye.getType());
+        assertEquals(Component.text("Eye of True Seeing"), eye.getItemMeta().displayName());
+        assertTrue(items.isEye(eye));
+        assertTrue(items.isEye(eye.clone()), "ordinary inventory transfer must retain item identity");
+        assertEquals(EquipmentSlot.HEAD, eye.getItemMeta().getEquippable().getSlot());
+        assertEquals(1, eye.getMaxStackSize());
+        assertFalse(eye.getItemMeta().getEquippable().isDispensable());
+        assertFalse(eye.getItemMeta().getEquippable().isEquipOnInteract(),
+                "the eligibility-checked interaction handler, not native item use, equips the Eye");
+        var ordinary = new ItemStack(Material.ENDER_EYE);
+        assertFalse(items.isEye(ordinary));
+        var renamed = ordinary.getItemMeta();
+        renamed.displayName(eye.getItemMeta().displayName());
+        ordinary.setItemMeta(renamed);
+        assertFalse(items.isEye(ordinary), "anvil/display names cannot authenticate an Eye");
+        var wrongMaterial = eye.clone();
+        wrongMaterial.setType(Material.STONE);
+        assertFalse(items.isEye(wrongMaterial));
+        assertFalse(items.isEye(null));
+    }
+}

src/nativeTest/java/games/dmg/spigotstealth/EyePluginLifecycleTest.java

@@ -0,0 +1,216 @@
+package games.dmg.spigotstealth;
+
+import static org.junit.jupiter.api.Assertions.*;
+import static org.mockito.Mockito.*;
+
+import com.comphenix.protocol.ProtocolLibrary;
+import com.comphenix.protocol.ProtocolManager;
+import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+import java.util.UUID;
+import java.util.concurrent.LinkedBlockingQueue;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicReference;
+import java.util.function.Consumer;
+import java.util.logging.Logger;
+import org.bukkit.Server;
+import org.bukkit.command.PluginCommand;
+import org.bukkit.configuration.file.YamlConfiguration;
+import org.bukkit.entity.Player;
+import org.bukkit.event.Event;
+import org.bukkit.event.EventHandler;
+import org.bukkit.event.Listener;
+import org.bukkit.event.inventory.PrepareItemCraftEvent;
+import org.bukkit.inventory.CraftingInventory;
+import org.bukkit.inventory.InventoryView;
+import org.bukkit.inventory.ItemStack;
+import org.bukkit.inventory.Recipe;
+import org.bukkit.plugin.EventExecutor;
+import org.bukkit.plugin.PluginDescriptionFile;
+import org.bukkit.plugin.PluginManager;
+import org.bukkit.plugin.RegisteredListener;
+import org.bukkit.scheduler.BukkitScheduler;
+import org.bukkit.scheduler.BukkitTask;
+import org.bukkit.scoreboard.Scoreboard;
+import org.bukkit.scoreboard.ScoreboardManager;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+
+class EyePluginLifecycleTest {
+    @TempDir Path directory;
+    @BeforeAll static void bootstrap() throws Exception { NativeRuntime.bootstrap(); }
+
+    @org.junit.jupiter.params.ParameterizedTest
+    @org.junit.jupiter.params.provider.ValueSource(strings = {"normal", "disabled", "reenabled", "presentation-failure"})
+    @SuppressWarnings("try") // The scoped Bukkit boundary delegates non-server-metadata operations to native code.
+    void startupAndLateCallbacksRespectSavedUnlocksAndDisable(String mode) throws Exception {
+        UUID id = UUID.randomUUID(), learner = UUID.randomUUID();
+        var disk = new YamlStealthStateRepository(directory.resolve("state.yml"));
+        disk.save(new PersistentStealthState(Map.of(), Map.of()).withEyeProgress(id, new EyeProgress(28_800_000, true)));
+        var plugin = mock(SpigotStealthPlugin.class, CALLS_REAL_METHODS);
+        var clock = new java.util.concurrent.atomic.AtomicLong();
+        doAnswer(ignored -> clock.get()).when(plugin).monotonicNanos();
+        Server server = mock(org.bukkit.craftbukkit.CraftServer.class);
+        var plugins = mock(PluginManager.class);
+        BukkitScheduler scheduler = mock(org.bukkit.craftbukkit.scheduler.CraftScheduler.class);
+        var player = mock(Player.class);
+        when(player.getUniqueId()).thenReturn(id);
+        doReturn(List.of(player)).when(server).getOnlinePlayers();
+        when(server.getPlayer(id)).thenReturn(player);
+        doReturn(server).when(plugin).getServer();
+        doReturn(true).when(plugin).isEnabled();
+        doReturn(directory.toFile()).when(plugin).getDataFolder();
+        doReturn(new YamlConfiguration()).when(plugin).getConfig();
+        doReturn(Logger.getAnonymousLogger()).when(plugin).getLogger();
+        doReturn(new PluginDescriptionFile("SpigotStealth", "test", SpigotStealthPlugin.class.getName()))
+                .when(plugin).getDescription();
+        doNothing().when(plugin).saveDefaultConfig();
+        doReturn(mock(PluginCommand.class)).when(plugin).getCommand("stealth");
+        doReturn(mock(PluginCommand.class)).when(plugin).getCommand("stealthadmin");
+        when(server.getPluginManager()).thenReturn(plugins);
+        when(server.getScheduler()).thenReturn(scheduler);
+        ScoreboardManager boards = mock(org.bukkit.craftbukkit.scoreboard.CraftScoreboardManager.class);
+        when(server.getScoreboardManager()).thenReturn(boards);
+        when(boards.getMainScoreboard()).thenReturn(mock(org.bukkit.craftbukkit.scoreboard.CraftScoreboard.class));
+        var main = new LinkedBlockingQueue<Runnable>();
+        when(scheduler.runTask(eq(plugin), any(Runnable.class))).thenAnswer(call -> {
+            main.add(call.getArgument(1)); return mock(BukkitTask.class);
+        });
+        var timers = new ArrayList<Runnable>();
+        doAnswer(call -> {
+            Consumer<BukkitTask> action = call.getArgument(1);
+            timers.add(() -> action.accept(mock(BukkitTask.class)));
+            return null;
+        }).when(scheduler).runTaskTimer(eq(plugin), org.mockito.ArgumentMatchers.<Consumer<BukkitTask>>any(), anyLong(), anyLong());
+        when(scheduler.runTaskTimer(eq(plugin), any(Runnable.class), anyLong(), anyLong())).thenAnswer(call -> {
+            timers.add(call.getArgument(1)); return mock(BukkitTask.class);
+        });
+        var recipe = new AtomicReference<Recipe>();
+        when(server.addRecipe(any(Recipe.class))).thenAnswer(call -> { recipe.set(call.getArgument(0)); return true; });
+        var listeners = new ArrayList<Listener>();
+        doAnswer(call -> { listeners.add(call.getArgument(0)); return null; }).when(plugins).registerEvents(any(), eq(plugin));
+        try (var platform = mockStatic(org.bukkit.Bukkit.class, call -> switch (call.getMethod().getName()) {
+            case "getServer" -> server;
+            case "getVersion" -> "Purpur 2618 (MC: 26.2)";
+            case "getMinecraftVersion" -> "26.2";
+            case "getBukkitVersion" -> "26.2-R0.1-SNAPSHOT";
+            default -> call.callRealMethod();
+        }); var protocol = mockStatic(ProtocolLibrary.class)) {
+            var protocolManager = mock(ProtocolManager.class);
+            protocol.when(ProtocolLibrary::getProtocolManager).thenReturn(protocolManager);
+            try {
+                plugin.onEnable();
+                assertNull(recipe.get(), "Bukkit registration must wait for durable state initialization and main-thread dispatch");
+                Runnable initialization = main.poll(3, TimeUnit.SECONDS);
+                assertNotNull(initialization);
+                if (mode.equals("disabled") || mode.equals("reenabled")) {
+                    doReturn(false).when(plugin).isEnabled();
+                    plugin.onDisable();
+                    if (mode.equals("reenabled")) {
+                        doReturn(true).when(plugin).isEnabled();
+                        plugin.onEnable();
+                        Runnable currentInitialization = main.poll(3, TimeUnit.SECONDS);
+                        assertNotNull(currentInitialization);
+                        currentInitialization.run();
+                        int registeredCount = listeners.size();
+                        assertNotNull(recipe.get());
+                        initialization.run();
+                        assertEquals(registeredCount, listeners.size(), "an old lifecycle callback must not touch a re-enabled plugin");
+                        verify(server, times(1)).addRecipe(any(Recipe.class));
+                        return;
+                    }
+                    initialization.run();
+                    assertTrue(listeners.isEmpty(), "a queued initialization must not register listeners after disable");
+                    assertNull(recipe.get());
+                    verify(server, never()).removeRecipe(any());
+                    return;
+                }
+                initialization.run();
+                assertNotNull(recipe.get(), "plugin startup must register the Eye recipe");
+                assertTrue(new EyeItems().isEye(recipe.get().getResult()));
+                assertTrue(listeners.stream().anyMatch(EyePotionListener.class::isInstance));
+                assertTrue(listeners.stream().anyMatch(EyeEquipment.class::isInstance));
+                var inventory = mock(CraftingInventory.class);
+                when(inventory.getRecipe()).thenAnswer(ignored -> recipe.get());
+                var result = new AtomicReference<>(recipe.get().getResult());
+                when(inventory.getResult()).thenAnswer(ignored -> result.get());
+                doAnswer(call -> { result.set(call.getArgument(0)); return null; }).when(inventory).setResult(any());
+                var view = mock(InventoryView.class);
+                when(view.getPlayer()).thenReturn(player);
+                when(view.getTopInventory()).thenReturn(inventory);
+                var prepare = new PrepareItemCraftEvent(inventory, view, false);
+                dispatch(plugin, listeners, prepare);
+                assertTrue(new EyeItems().isEye(result.get()), "the restored personal unlock must permit crafting");
+                when(player.getUniqueId()).thenReturn(learner);
+                when(server.getPlayer(learner)).thenReturn(player);
+                dispatch(plugin, listeners, prepare);
+                assertNull(result.get(), "registered handlers must deny an unearned player's result");
+                var effect = new org.bukkit.potion.PotionEffect(org.bukkit.potion.PotionEffectType.NIGHT_VISION, 9600, 0);
+                dispatch(plugin, listeners, new org.bukkit.event.entity.EntityPotionEffectEvent(player, null, effect, player,
+                        org.bukkit.event.entity.EntityPotionEffectEvent.Cause.POTION_DRINK,
+                        org.bukkit.event.entity.EntityPotionEffectEvent.Action.ADDED, false));
+                clock.set(java.time.Duration.ofHours(8).toNanos());
+                dispatch(plugin, listeners, new org.bukkit.event.entity.EntityPotionEffectEvent(player, effect, null, null,
+                        org.bukkit.event.entity.EntityPotionEffectEvent.Cause.EXPIRATION,
+                        org.bukkit.event.entity.EntityPotionEffectEvent.Action.REMOVED, false));
+                Runnable unlocked = main.poll(3, TimeUnit.SECONDS);
+                assertNotNull(unlocked, "the registered potion listener must persist the unlock and schedule its notification");
+                assertTrue(disk.load().eyeProgress(learner).unlocked());
+                unlocked.run();
+                result.set(recipe.get().getResult());
+                dispatch(plugin, listeners, prepare);
+                assertTrue(new EyeItems().isEye(result.get()), "the registered crafting listener must see the newly saved unlock");
+                clearInvocations(player);
+                when(player.getUniqueId()).thenReturn(id);
+                timers.forEach(Runnable::run);
+                verify(player).discoverRecipe(EyeCrafting.RECIPE_KEY);
+                // Disable must checkpoint and drain an in-flight qualifying interval, not just remove the recipe.
+                when(player.getUniqueId()).thenReturn(learner);
+                when(player.isOnline()).thenReturn(true);
+                when(player.getPotionEffect(org.bukkit.potion.PotionEffectType.NIGHT_VISION)).thenReturn(effect);
+                dispatch(plugin, listeners, new org.bukkit.event.entity.EntityPotionEffectEvent(player, null, effect, player,
+                        org.bukkit.event.entity.EntityPotionEffectEvent.Cause.POTION_DRINK,
+                        org.bukkit.event.entity.EntityPotionEffectEvent.Action.ADDED, false));
+                clock.addAndGet(1_234_000_000L);
+            } finally {
+                if (mode.equals("presentation-failure")) {
+                    doThrow(new IllegalStateException("Injected presentation cleanup failure"))
+                            .when(protocolManager).removePacketListeners(plugin);
+                    try {
+                        assertThrows(IllegalStateException.class, plugin::onDisable);
+                        plugin.shutdownCompletion().get(3, TimeUnit.SECONDS);
+                        assertEquals(28_801_234, disk.load().eyeProgress(learner).accumulatedMillis(),
+                                "presentation cleanup failure must not prevent Eye progress from draining");
+                    } finally {
+                        doNothing().when(protocolManager).removePacketListeners(plugin);
+                        plugin.onDisable();
+                        plugin.shutdownCompletion().get(3, TimeUnit.SECONDS);
+                    }
+                } else {
+                    plugin.onDisable();
+                    plugin.shutdownCompletion().get(3, TimeUnit.SECONDS);
+                }
+            }
+        }
+        verify(server).removeRecipe(EyeCrafting.RECIPE_KEY);
+        assertEquals(28_801_234, disk.load().eyeProgress(learner).accumulatedMillis());
+    }
+
+    private static void dispatch(SpigotStealthPlugin plugin, List<Listener> listeners, Event event) throws Exception {
+        var registered = new ArrayList<RegisteredListener>();
+        for (var listener : listeners) {
+            for (var method : listener.getClass().getMethods()) {
+                var handler = method.getAnnotation(EventHandler.class);
+                if (handler == null || method.getParameterCount() != 1 || !method.getParameterTypes()[0].isInstance(event)) { continue; }
+                registered.add(new RegisteredListener(listener,
+                        EventExecutor.create(method, method.getParameterTypes()[0].asSubclass(Event.class)),
+                        handler.priority(), plugin, handler.ignoreCancelled()));
+            }
+        }
+        registered.sort(java.util.Comparator.comparing(RegisteredListener::getPriority));
+        for (var handler : registered) { handler.callEvent(event); }
+    }
+}

src/nativeTest/java/games/dmg/spigotstealth/EyePotionProgressionTest.java

@@ -0,0 +1,302 @@
+package games.dmg.spigotstealth;
+
+import static org.junit.jupiter.api.Assertions.*;
+import static org.mockito.Mockito.*;
+
+import java.nio.file.Path;
+import java.time.Duration;
+import java.util.UUID;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicLong;
+import org.bukkit.entity.Player;
+import org.bukkit.event.entity.EntityPotionEffectEvent;
+import org.bukkit.potion.PotionEffect;
+import org.bukkit.potion.PotionEffectType;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+
+/** Real Purpur effect/event objects, real progression/persistence, only player and clock are external doubles. */
+class EyePotionProgressionTest {
+    @TempDir Path directory;
+    @BeforeAll static void bootstrap() throws Exception { NativeRuntime.bootstrap(); }
+
+    @Test
+    void aTransitionBeforeTheNextObservationCannotCreditAnUnattributedRestoredEffect() throws Exception {
+        for (String transition : java.util.List.of("quit", "remove", "refresh")) {
+            UUID id = UUID.randomUUID();
+            var player = mock(Player.class);
+            when(player.getUniqueId()).thenReturn(id);
+            when(player.isOnline()).thenReturn(true);
+            var clock = new AtomicLong();
+            var repository = new YamlStealthStateRepository(directory.resolve(transition + ".yml"));
+            try (var states = new StealthStateManager(repository, repository.load())) {
+                var progression = new EyeProgressionService(states, clock::get, ignored -> { });
+                var listener = new EyePotionListener(progression, failure -> fail(failure));
+                var strong = new PotionEffect(PotionEffectType.NIGHT_VISION, 100, 1);
+                var restored = new PotionEffect(PotionEffectType.NIGHT_VISION, 400, 0);
+                listener.onPotionEffect(new EntityPotionEffectEvent(player, null, strong, player,
+                        EntityPotionEffectEvent.Cause.POTION_DRINK, EntityPotionEffectEvent.Action.ADDED, false));
+                when(player.getPotionEffect(PotionEffectType.NIGHT_VISION)).thenReturn(strong);
+                clock.set(Duration.ofSeconds(1).toNanos());
+                listener.checkpoint(ignored -> player);
+                clock.set(Duration.ofSeconds(3).toNanos());
+                when(player.getPotionEffect(PotionEffectType.NIGHT_VISION)).thenReturn(restored);
+                switch (transition) {
+                    case "quit" -> listener.onQuit(new org.bukkit.event.player.PlayerQuitEvent(
+                            player, net.kyori.adventure.text.Component.empty()));
+                    case "remove" -> listener.onPotionEffect(new EntityPotionEffectEvent(player, restored, null, null,
+                            EntityPotionEffectEvent.Cause.EXPIRATION, EntityPotionEffectEvent.Action.REMOVED, false));
+                    case "refresh" -> listener.onPotionEffect(new EntityPotionEffectEvent(player, restored,
+                            new PotionEffect(PotionEffectType.NIGHT_VISION, 800, 0), player,
+                            EntityPotionEffectEvent.Cause.POTION_DRINK, EntityPotionEffectEvent.Action.CHANGED, true));
+                    default -> throw new AssertionError(transition);
+                }
+                states.save().get(3, TimeUnit.SECONDS);
+                assertEquals(1000, repository.load().eyeProgress(id).accumulatedMillis(), transition);
+            }
+        }
+    }
+
+    @Test
+    void periodicObservationStopsAtUnattributedHiddenEffectRestorationOrMissingPlayer() throws Exception {
+        UUID id = UUID.randomUUID();
+        var player = mock(Player.class);
+        when(player.getUniqueId()).thenReturn(id);
+        when(player.isOnline()).thenReturn(true);
+        var clock = new AtomicLong();
+        var repository = new YamlStealthStateRepository(directory.resolve("state.yml"));
+        try (var states = new StealthStateManager(repository, repository.load())) {
+            var progression = new EyeProgressionService(states, clock::get, ignored -> { });
+            var listener = new EyePotionListener(progression, failure -> fail(failure));
+            var strong = new PotionEffect(PotionEffectType.NIGHT_VISION, 100, 1);
+            listener.onPotionEffect(new EntityPotionEffectEvent(player, null, strong, player,
+                    EntityPotionEffectEvent.Cause.POTION_DRINK, EntityPotionEffectEvent.Action.ADDED, false));
+            when(player.getPotionEffect(PotionEffectType.NIGHT_VISION)).thenReturn(
+                    new PotionEffect(PotionEffectType.NIGHT_VISION, 80, 1));
+            clock.set(Duration.ofSeconds(1).toNanos());
+            listener.checkpoint(ignored -> player);
+            states.save().get(3, TimeUnit.SECONDS);
+            assertEquals(1000, repository.load().eyeProgress(id).accumulatedMillis());
+            // Native hidden-effect promotion need not emit a new potion-source event.
+            when(player.getPotionEffect(PotionEffectType.NIGHT_VISION)).thenReturn(
+                    new PotionEffect(PotionEffectType.NIGHT_VISION, 400, 0));
+            clock.set(Duration.ofSeconds(2).toNanos());
+            listener.checkpoint(ignored -> player);
+            clock.set(Duration.ofHours(12).toNanos());
+            listener.checkpoint(ignored -> player);
+            states.save().get(3, TimeUnit.SECONDS);
+            assertEquals(1000, repository.load().eyeProgress(id).accumulatedMillis(),
+                    "unattributed restored effects must not inherit the drink timer");
+            assertTrue(progression.activePlayerIds().isEmpty());
+            listener.onPotionEffect(new EntityPotionEffectEvent(player, null, strong, player,
+                    EntityPotionEffectEvent.Cause.POTION_DRINK, EntityPotionEffectEvent.Action.ADDED, false));
+            clock.addAndGet(Duration.ofDays(1).toNanos());
+            listener.checkpoint(ignored -> null);
+            states.save().get(3, TimeUnit.SECONDS);
+            assertEquals(1000, repository.load().eyeProgress(id).accumulatedMillis());
+            assertTrue(progression.activePlayerIds().isEmpty());
+        }
+    }
+
+    @Test
+    void disconnectClosesTheIntervalAndRestartDoesNotCountTheOfflineGap() throws Exception {
+        UUID id = UUID.randomUUID();
+        var player = mock(Player.class);
+        when(player.getUniqueId()).thenReturn(id);
+        var clock = new AtomicLong();
+        var repository = new YamlStealthStateRepository(directory.resolve("state.yml"));
+        try (var states = new StealthStateManager(repository, repository.load())) {
+            var progression = new EyeProgressionService(states, clock::get, ignored -> { });
+            var listener = new EyePotionListener(progression, failure -> fail(failure));
+            var effect = new PotionEffect(PotionEffectType.NIGHT_VISION, 200, 0);
+            listener.onPotionEffect(new EntityPotionEffectEvent(player, null, effect, player,
+                    EntityPotionEffectEvent.Cause.POTION_DRINK, EntityPotionEffectEvent.Action.ADDED, false));
+            clock.set(Duration.ofSeconds(1).toNanos());
+            when(player.getPotionEffect(PotionEffectType.NIGHT_VISION)).thenReturn(effect);
+            listener.onQuit(new org.bukkit.event.player.PlayerQuitEvent(player, net.kyori.adventure.text.Component.empty()));
+            clock.addAndGet(Duration.ofDays(7).toNanos());
+            progression.checkpoint(id).get(3, TimeUnit.SECONDS);
+            states.save().get(3, TimeUnit.SECONDS);
+            assertEquals(1000, repository.load().eyeProgress(id).accumulatedMillis(),
+                    "disconnect must close the qualifying interval before offline time passes");
+            assertFalse(progression.isUnlocked(id));
+        }
+        try (var restarted = new StealthStateManager(repository, repository.load())) {
+            var progression = new EyeProgressionService(restarted, clock::get, ignored -> { });
+            assertEquals(1000, restarted.snapshot().eyeProgress(id).accumulatedMillis());
+            assertTrue(progression.activePlayerIds().isEmpty());
+            assertFalse(progression.isUnlocked(id));
+        }
+    }
+
+    @Test
+    void everyNonDrinkSourceIsExcludedAndAnEffectiveExternalReplacementStopsCredit() throws Exception {
+        UUID id = UUID.randomUUID();
+        var player = mock(Player.class);
+        when(player.getUniqueId()).thenReturn(id);
+        var clock = new AtomicLong();
+        var repository = new YamlStealthStateRepository(directory.resolve("state.yml"));
+        try (var states = new StealthStateManager(repository, repository.load())) {
+            var progression = new EyeProgressionService(states, clock::get, ignored -> { });
+            var listener = new EyePotionListener(progression, failure -> fail(failure));
+            var effect = new PotionEffect(PotionEffectType.NIGHT_VISION, 200, 0);
+            for (var cause : EntityPotionEffectEvent.Cause.values()) {
+                if (cause == EntityPotionEffectEvent.Cause.POTION_DRINK) { continue; }
+                listener.onPotionEffect(new EntityPotionEffectEvent(player, null, effect, null,
+                        cause, EntityPotionEffectEvent.Action.ADDED, false));
+                clock.addAndGet(Duration.ofSeconds(1).toNanos());
+                progression.checkpoint(id).get(3, TimeUnit.SECONDS);
+                assertEquals(0, states.snapshot().eyeProgress(id).accumulatedMillis(), cause.toString());
+                listener.onPotionEffect(new EntityPotionEffectEvent(player, effect, null, null,
+                        EntityPotionEffectEvent.Cause.EXPIRATION, EntityPotionEffectEvent.Action.REMOVED, false));
+            }
+            listener.onPotionEffect(new EntityPotionEffectEvent(player, null, effect, player,
+                    EntityPotionEffectEvent.Cause.POTION_DRINK, EntityPotionEffectEvent.Action.ADDED, false));
+            clock.addAndGet(Duration.ofSeconds(1).toNanos());
+            listener.onPotionEffect(new EntityPotionEffectEvent(player, effect,
+                    new PotionEffect(PotionEffectType.NIGHT_VISION, 400, 0), null,
+                    EntityPotionEffectEvent.Cause.PLUGIN, EntityPotionEffectEvent.Action.CHANGED, true));
+            clock.addAndGet(Duration.ofHours(12).toNanos());
+            progression.checkpoint(id).get(3, TimeUnit.SECONDS);
+            states.save().get(3, TimeUnit.SECONDS);
+            assertEquals(1000, repository.load().eyeProgress(id).accumulatedMillis());
+            assertFalse(progression.isUnlocked(id));
+        }
+    }
+
+    @Test
+    void cancelledAndUnrelatedEffectEventsCannotStartOrInterruptCredit() throws Exception {
+        UUID id = UUID.randomUUID();
+        var player = mock(Player.class);
+        when(player.getUniqueId()).thenReturn(id);
+        var clock = new AtomicLong();
+        var repository = new YamlStealthStateRepository(directory.resolve("state.yml"));
+        try (var states = new StealthStateManager(repository, repository.load())) {
+            var progression = new EyeProgressionService(states, clock::get, ignored -> { });
+            var listener = new EyePotionListener(progression, failure -> fail(failure));
+            var effect = new PotionEffect(PotionEffectType.NIGHT_VISION, 200, 0);
+            var cancelled = new EntityPotionEffectEvent(player, null, effect, player,
+                    EntityPotionEffectEvent.Cause.POTION_DRINK, EntityPotionEffectEvent.Action.ADDED, false);
+            cancelled.setCancelled(true);
+            listener.onPotionEffect(cancelled);
+            clock.set(Duration.ofSeconds(1).toNanos());
+            progression.checkpoint(id).get(3, TimeUnit.SECONDS);
+            assertEquals(0, states.snapshot().eyeProgress(id).accumulatedMillis());
+            cancelled.setCancelled(false);
+            listener.onPotionEffect(cancelled);
+            clock.set(Duration.ofSeconds(2).toNanos());
+            var cancelledRemoval = new EntityPotionEffectEvent(player, effect, null, null,
+                    EntityPotionEffectEvent.Cause.MILK, EntityPotionEffectEvent.Action.CLEARED, false);
+            cancelledRemoval.setCancelled(true);
+            listener.onPotionEffect(cancelledRemoval);
+            listener.onPotionEffect(new EntityPotionEffectEvent(player, null,
+                    new PotionEffect(PotionEffectType.INVISIBILITY, 200, 0), null,
+                    EntityPotionEffectEvent.Cause.PLUGIN, EntityPotionEffectEvent.Action.ADDED, false));
+            clock.set(Duration.ofSeconds(3).toNanos());
+            progression.stop(id).get(3, TimeUnit.SECONDS);
+            assertEquals(2000, repository.load().eyeProgress(id).accumulatedMillis());
+        }
+    }
+
+    @Test
+    void cosmeticOnlyOverridesDoNotReassignTheActiveEffectsSource() throws Exception {
+        // Purpur reports override=true even when only particle/icon flags change.
+        var nativeActive = new net.minecraft.world.effect.MobEffectInstance(
+                net.minecraft.world.effect.MobEffects.NIGHT_VISION, 200, 1);
+        assertTrue(nativeActive.update(new net.minecraft.world.effect.MobEffectInstance(
+                net.minecraft.world.effect.MobEffects.NIGHT_VISION, 100, 0, false, false, false)));
+        assertEquals(1, nativeActive.getAmplifier());
+        assertEquals(200, nativeActive.getDuration());
+        UUID id = UUID.randomUUID();
+        var player = mock(Player.class);
+        when(player.getUniqueId()).thenReturn(id);
+        var clock = new AtomicLong();
+        var repository = new YamlStealthStateRepository(directory.resolve("state.yml"));
+        try (var states = new StealthStateManager(repository, repository.load())) {
+            var progression = new EyeProgressionService(states, clock::get, ignored -> { });
+            var listener = new EyePotionListener(progression, failure -> fail(failure));
+            var weak = new PotionEffect(PotionEffectType.NIGHT_VISION, 100, 0, false, false, false);
+            var strong = new PotionEffect(PotionEffectType.NIGHT_VISION, 200, 1);
+            listener.onPotionEffect(new EntityPotionEffectEvent(player, strong, weak, player,
+                    EntityPotionEffectEvent.Cause.POTION_DRINK, EntityPotionEffectEvent.Action.CHANGED, true));
+            clock.set(Duration.ofSeconds(1).toNanos());
+            progression.checkpoint(id).get(3, TimeUnit.SECONDS);
+            assertEquals(0, states.snapshot().eyeProgress(id).accumulatedMillis(),
+                    "a cosmetic drink change must not claim the stronger existing effect");
+            listener.onPotionEffect(new EntityPotionEffectEvent(player, null, strong, player,
+                    EntityPotionEffectEvent.Cause.POTION_DRINK, EntityPotionEffectEvent.Action.ADDED, false));
+            clock.set(Duration.ofSeconds(2).toNanos());
+            listener.onPotionEffect(new EntityPotionEffectEvent(player, strong, weak, null,
+                    EntityPotionEffectEvent.Cause.PLUGIN, EntityPotionEffectEvent.Action.CHANGED, true));
+            clock.set(Duration.ofSeconds(3).toNanos());
+            listener.onPotionEffect(new EntityPotionEffectEvent(player, strong, null, null,
+                    EntityPotionEffectEvent.Cause.EXPIRATION, EntityPotionEffectEvent.Action.REMOVED, false));
+            states.save().get(3, TimeUnit.SECONDS);
+            assertEquals(2000, states.snapshot().eyeProgress(id).accumulatedMillis());
+        }
+    }
+
+    @Test
+    void rejectedReplacementsNeitherStartNorStopQualifyingTime() throws Exception {
+        UUID id = UUID.randomUUID();
+        var player = mock(Player.class);
+        when(player.getUniqueId()).thenReturn(id);
+        var clock = new AtomicLong();
+        var repository = new YamlStealthStateRepository(directory.resolve("state.yml"));
+        try (var states = new StealthStateManager(repository, repository.load())) {
+            var progression = new EyeProgressionService(states, clock::get, ignored -> { });
+            var listener = new EyePotionListener(progression, failure -> fail(failure));
+            var weak = new PotionEffect(PotionEffectType.NIGHT_VISION, 100, 0);
+            var strong = new PotionEffect(PotionEffectType.NIGHT_VISION, 200, 1);
+            listener.onPotionEffect(new EntityPotionEffectEvent(player, strong, weak, player,
+                    EntityPotionEffectEvent.Cause.POTION_DRINK, EntityPotionEffectEvent.Action.CHANGED, false));
+            clock.set(Duration.ofSeconds(1).toNanos());
+            progression.checkpoint(id).get(3, TimeUnit.SECONDS);
+            assertEquals(0, states.snapshot().eyeProgress(id).accumulatedMillis(),
+                    "a rejected drink must not claim an existing non-drink effect");
+            listener.onPotionEffect(new EntityPotionEffectEvent(player, null, strong, player,
+                    EntityPotionEffectEvent.Cause.POTION_DRINK, EntityPotionEffectEvent.Action.ADDED, false));
+            clock.set(Duration.ofSeconds(2).toNanos());
+            listener.onPotionEffect(new EntityPotionEffectEvent(player, strong, weak, null,
+                    EntityPotionEffectEvent.Cause.PLUGIN, EntityPotionEffectEvent.Action.CHANGED, false));
+            clock.set(Duration.ofSeconds(3).toNanos());
+            listener.onPotionEffect(new EntityPotionEffectEvent(player, strong, null, null,
+                    EntityPotionEffectEvent.Cause.EXPIRATION, EntityPotionEffectEvent.Action.REMOVED, false));
+            states.save().get(3, TimeUnit.SECONDS);
+            assertEquals(2000, states.snapshot().eyeProgress(id).accumulatedMillis(),
+                    "a rejected plugin replacement must not interrupt the effective drunk potion");
+        }
+    }
+
+    @Test
+    void effectiveDirectDrinkAccumulatesAcrossRefreshAndDurablyUnlocksAtEightHours() throws Exception {
+        UUID id = UUID.randomUUID();
+        var player = mock(Player.class);
+        when(player.getUniqueId()).thenReturn(id);
+        var clock = new AtomicLong();
+        var repository = new YamlStealthStateRepository(directory.resolve("state.yml"));
+        try (var states = new StealthStateManager(repository, repository.load())) {
+            var progression = new EyeProgressionService(states, clock::get, ignored -> { });
+            var listener = new EyePotionListener(progression, failure -> fail(failure));
+            var nightVision = new PotionEffect(PotionEffectType.NIGHT_VISION, 9600, 0);
+            listener.onPotionEffect(new EntityPotionEffectEvent(player, null, nightVision, player,
+                    EntityPotionEffectEvent.Cause.POTION_DRINK, EntityPotionEffectEvent.Action.ADDED, true));
+            for (int refresh = 1; refresh < 60; refresh++) {
+                clock.set(Duration.ofSeconds(refresh * 480L).toNanos());
+                listener.onPotionEffect(new EntityPotionEffectEvent(player, new PotionEffect(PotionEffectType.NIGHT_VISION, 1, 0), nightVision, player,
+                        EntityPotionEffectEvent.Cause.POTION_DRINK, EntityPotionEffectEvent.Action.CHANGED, true));
+            }
+            clock.set(Duration.ofHours(8).toNanos() - 1_000_000);
+            progression.checkpoint(id).get(3, TimeUnit.SECONDS);
+            assertFalse(progression.isUnlocked(id));
+            clock.addAndGet(1_000_000);
+            listener.onPotionEffect(new EntityPotionEffectEvent(player, nightVision, null, null,
+                    EntityPotionEffectEvent.Cause.EXPIRATION, EntityPotionEffectEvent.Action.REMOVED, false));
+            states.save().get(3, TimeUnit.SECONDS);
+            assertTrue(progression.isUnlocked(id), "eight hours of effective drink events must unlock the Eye");
+            assertEquals(28_800_000, repository.load().eyeProgress(id).accumulatedMillis());
+            assertTrue(progression.activePlayerIds().isEmpty());
+        }
+    }
+}

src/nativeTest/java/games/dmg/spigotstealth/NativeRuntime.java

@@ -0,0 +1,61 @@
+package games.dmg.spigotstealth;
+
+import java.util.List;
+import java.util.stream.Stream;
+import net.minecraft.SharedConstants;
+import net.minecraft.commands.Commands;
+import net.minecraft.core.HolderLookup;
+import net.minecraft.core.LayeredRegistryAccess;
+import net.minecraft.core.Registry;
+import net.minecraft.core.RegistryAccess;
+import net.minecraft.resources.Identifier;
+import net.minecraft.resources.RegistryDataLoader;
+import net.minecraft.server.Bootstrap;
+import net.minecraft.server.MinecraftServer;
+import net.minecraft.server.RegistryLayer;
+import net.minecraft.server.ReloadableServerResources;
+import net.minecraft.server.packs.PackType;
+import net.minecraft.server.packs.repository.ServerPacksSource;
+import net.minecraft.server.packs.resources.MultiPackResourceManager;
+import net.minecraft.server.permissions.LevelBasedPermissionSet;
+import net.minecraft.tags.TagLoader;
+import net.minecraft.util.Util;
+import net.minecraft.world.flag.FeatureFlags;
+import net.minecraft.world.level.DataPackConfig;
+import net.minecraft.world.level.WorldDataConfiguration;
+import org.bukkit.craftbukkit.CraftRegistry;
+
+/** Loads vanilla registries/tags/components using the same path as the server's own tests. */
+final class NativeRuntime {
+    private NativeRuntime() {}
+    private static boolean ready;
+
+    static synchronized void bootstrap() throws Exception {
+        if (ready) { return; }
+        SharedConstants.tryDetectVersion();
+        Bootstrap.bootStrap();
+        var flags = FeatureFlags.VANILLA_SET;
+        var packs = ServerPacksSource.createVanillaTrustedRepository();
+        MinecraftServer.configurePackRepository(packs, new WorldDataConfiguration(new DataPackConfig(
+                FeatureFlags.REGISTRY.toNames(flags).stream().map(Identifier::getPath).toList(), List.of()), flags), true, false);
+        try (var resources = new MultiPackResourceManager(PackType.SERVER_DATA, packs.openAllSelected())) {
+            LayeredRegistryAccess<RegistryLayer> layers = RegistryLayer.createRegistryAccess();
+            List<Registry.PendingTags<?>> tags = TagLoader.loadTagsForExistingRegistries(resources, layers.getLayer(RegistryLayer.STATIC));
+            List<HolderLookup.RegistryLookup<?>> lookups = TagLoader.buildUpdatedLookups(layers.getAccessForLoading(RegistryLayer.WORLDGEN), tags);
+            RegistryAccess.Frozen worldgen = RegistryDataLoader.load(resources, lookups,
+                    RegistryDataLoader.WORLDGEN_REGISTRIES, Util.backgroundExecutor()).join();
+            layers = layers.replaceFrom(RegistryLayer.WORLDGEN, worldgen);
+            RegistryAccess.Frozen dimensions = RegistryDataLoader.load(resources,
+                    Stream.concat(lookups.stream(), worldgen.listRegistries()).toList(),
+                    RegistryDataLoader.DIMENSION_REGISTRIES, Util.backgroundExecutor()).join();
+            layers = layers.replaceFrom(RegistryLayer.DIMENSIONS, dimensions);
+            Class.forName(org.bukkit.Registry.class.getName());
+            var datapack = ReloadableServerResources.loadResources(resources, layers, tags, flags,
+                    Commands.CommandSelection.DEDICATED, LevelBasedPermissionSet.ALL_PERMISSIONS,
+                    Util.backgroundExecutor(), Runnable::run).join();
+            datapack.updateComponentsAndStaticRegistryTags();
+            CraftRegistry.setMinecraftRegistry(layers.compositeAccess().freeze());
+        }
+        ready = true;
+    }
+}

src/test/java/games/dmg/spigotstealth/BukkitIdentityPresentationTest.java

@@ -25,10 +25,14 @@ class BukkitIdentityPresentationTest {
         BukkitIdentityPresentation presentation = new BukkitIdentityPresentation(
                 () -> List.of(target), scoreboard, mock(TabListController.class));
 
+        when(target.getDisplayName()).thenReturn("Original Alex");
+        presentation.conceal(target);
         presentation.conceal(target);
         presentation.reveal(target);
 
-        verify(target).setSleepingIgnored(true);
+        verify(target).setDisplayName("Original Alex");
+        org.junit.jupiter.api.Assertions.assertTrue(presentation.concealedNames().isEmpty());
+        verify(target, org.mockito.Mockito.times(2)).setSleepingIgnored(true);
         verify(target).setSleepingIgnored(false);
     }
 
@@ -73,7 +77,7 @@ class BukkitIdentityPresentationTest {
     }
 
     @Test
-    void concealRemovesTabEntryAndHidesNameTagWithoutHidingEntity() {
+    void concealRemovesTabEntryAndScramblesNameTagWithoutHidingEntity() {
         UUID targetId = UUID.randomUUID();
         Player target = player(targetId, "Alex");
         Player observer = player(UUID.randomUUID(), "Morgan");
@@ -87,7 +91,11 @@ class BukkitIdentityPresentationTest {
 
         presentation.conceal(target);
 
-        verify(team).setOption(Team.Option.NAME_TAG_VISIBILITY, Team.OptionStatus.NEVER);
+        verify(team).setOption(Team.Option.NAME_TAG_VISIBILITY, Team.OptionStatus.ALWAYS);
+        verify(team).setPrefix("§k");
+        verify(team).setSuffix("§r");
+        verify(target).setDisplayName("§kAnonymous§r");
+        org.junit.jupiter.api.Assertions.assertEquals(java.util.Set.of("Alex"), presentation.concealedNames());
         verify(team).addEntry("Alex");
         verify(tabLists).remove(observer, targetId);
         verify(observer, never()).hidePlayer(org.mockito.ArgumentMatchers.any(), org.mockito.ArgumentMatchers.any());

src/test/java/games/dmg/spigotstealth/DeliveryConfigurationTest.java

@@ -13,7 +13,7 @@ class DeliveryConfigurationTest {
         String workflow = Files.readString(Path.of(".gitea/workflows/ci.yml"));
         assertTrue(workflow.contains("./gradlew clean check jar"));
         assertTrue(workflow.contains("commitlint"));
-        assertTrue(workflow.contains("spigot-stealth-${{ github.sha }}"));
+        assertTrue(workflow.contains("purpur-stealth-${{ github.sha }}"));
     }
 
     @Test
@@ -21,7 +21,7 @@ class DeliveryConfigurationTest {
         String workflow = Files.readString(Path.of(".gitea/workflows/release.yml"));
         assertTrue(workflow.contains("semantic-release"));
         assertTrue(workflow.contains("-PreleaseVersion=\"$VERSION\""));
-        assertTrue(workflow.contains("spigot-stealth-${VERSION}.jar"));
+        assertTrue(workflow.contains("purpur-stealth-${VERSION}.jar"));
         assertTrue(workflow.contains("/releases/${release_id}/assets"));
     }
 }

src/test/java/games/dmg/spigotstealth/EyeProgressStateTest.java

@@ -0,0 +1,37 @@
+package games.dmg.spigotstealth;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.UUID;
+import org.junit.jupiter.api.Test;
+
+class EyeProgressStateTest {
+    @Test
+    void eyeProgressRemainsIndependentAcrossExistingStealthAndSleepUpdates() {
+        UUID id = UUID.randomUUID();
+        var original = new PersistentStealthState(Map.of(), Map.of("future-root", "preserved"));
+        var eye = new EyeProgress(28_800_123, true, Map.of("future-eye", "preserved"));
+        var withEye = original.withEyeProgress(id, eye);
+        assertEquals(eye, withEye.eyeProgress(id));
+        assertEquals(EyeProgress.empty(), original.eyeProgress(id), "Updates must leave old snapshots immutable");
+        var changed = withEye.withPlayer(PlayerStealthState.empty(id).withProgress(123, true))
+            .withSleepCountPolicy(SleepCountPolicy.INCLUDE);
+        assertEquals(eye, changed.eyeProgress(id));
+        assertEquals(123, changed.player(id).accumulatedMillis());
+        assertEquals("preserved", changed.unknownFields().get("future-root"));
+        assertEquals(EyeProgress.empty(), changed.eyeProgress(UUID.randomUUID()));
+    }
+
+    @Test
+    void progressRejectsNegativeTimeAndCopiesUnknownFields() {
+        assertThrows(IllegalArgumentException.class, () -> new EyeProgress(-1, false));
+        var extras = new HashMap<String, Object>();
+        extras.put("extension", "old");
+        var progress = new EyeProgress(1, false, extras);
+        extras.put("extension", "new");
+        assertEquals("old", progress.unknownFields().get("extension"));
+        assertThrows(UnsupportedOperationException.class, () -> progress.unknownFields().put("other", 1));
+    }
+}

src/test/java/games/dmg/spigotstealth/EyeProgressionServiceTest.java

@@ -0,0 +1,90 @@
+package games.dmg.spigotstealth;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import java.nio.file.Path;
+import java.time.Duration;
+import java.util.List;
+import java.util.Map;
+import java.util.UUID;
+import java.util.concurrent.CopyOnWriteArrayList;
+import java.util.concurrent.atomic.AtomicLong;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+
+class EyeProgressionServiceTest {
+    @TempDir Path directory;
+    private final UUID id = UUID.randomUUID();
+    private final AtomicLong clock = new AtomicLong();
+    private final List<UUID> notifications = new CopyOnWriteArrayList<>();
+
+    @Test
+    void exactEightHoursUnlocksOnceWithoutOverlapOrLostSubmillisecondCredit() throws Exception {
+        var repository = new YamlStealthStateRepository(directory.resolve("state.yml"));
+        try (var states = new StealthStateManager(repository, repository.load())) {
+            var progression = new EyeProgressionService(states, clock::get, notifications::add);
+            progression.begin(id).join();
+            clock.set(600_000);
+            progression.checkpoint(id).join();
+            clock.set(1_200_000);
+            progression.begin(id).join(); // A refresh, not an overlapping timer.
+            assertEquals(1, states.snapshot().eyeProgress(id).accumulatedMillis());
+            clock.set(Duration.ofHours(8).toNanos() - 1);
+            progression.checkpoint(id).join();
+            assertFalse(progression.isUnlocked(id));
+            clock.incrementAndGet();
+            progression.checkpoint(id).join();
+            assertTrue(progression.isUnlocked(id));
+            assertEquals(List.of(id), notifications);
+            clock.addAndGet(Duration.ofSeconds(3).toNanos());
+            progression.stop(id).join();
+            assertEquals(28_803_000, states.snapshot().eyeProgress(id).accumulatedMillis());
+            assertEquals(List.of(id), notifications);
+            assertTrue(progression.activePlayerIds().isEmpty());
+        }
+    }
+
+    @Test
+    void intervalsAndRestartPreserveProgressWithoutOfflineOrUnobservedCredit() throws Exception {
+        var repository = new YamlStealthStateRepository(directory.resolve("state.yml"));
+        try (var states = new StealthStateManager(repository, repository.load())) {
+            var progression = new EyeProgressionService(states, clock::get, notifications::add);
+            progression.begin(id).join();
+            clock.addAndGet(Duration.ofHours(2).toNanos());
+            progression.stop(id).join();
+            clock.addAndGet(Duration.ofDays(30).toNanos());
+            progression.checkpoint(id).join();
+            assertEquals(Duration.ofHours(2).toMillis(), states.snapshot().eyeProgress(id).accumulatedMillis());
+        }
+        try (var states = new StealthStateManager(repository, repository.load())) {
+            var restarted = new EyeProgressionService(states, clock::get, notifications::add);
+            assertTrue(restarted.activePlayerIds().isEmpty());
+            restarted.begin(id).join();
+            clock.addAndGet(Duration.ofHours(6).toNanos());
+            restarted.stopAll().join();
+            assertTrue(restarted.isUnlocked(id));
+            assertEquals(28_800_000, repository.load().eyeProgress(id).accumulatedMillis());
+            assertTrue(restarted.activePlayerIds().isEmpty());
+        }
+    }
+
+    @Test
+    void missingDisconnectObservationDiscardsUnobservedTailAndExistingUnlocksDoNotRenotify() throws Exception {
+        var repository = new YamlStealthStateRepository(directory.resolve("state.yml"));
+        var existing = new PersistentStealthState(Map.of(), Map.of())
+            .withEyeProgress(id, new EyeProgress(28_800_000, true));
+        try (var states = new StealthStateManager(repository, existing)) {
+            var progression = new EyeProgressionService(states, clock::get, notifications::add);
+            assertTrue(progression.isUnlocked(id));
+            progression.begin(id).join();
+            clock.addAndGet(Duration.ofSeconds(1).toNanos());
+            progression.checkpoint(id).join();
+            clock.addAndGet(Duration.ofHours(1).toNanos());
+            progression.abandon(id);
+            progression.checkpoint(id).join();
+            assertEquals(28_801_000, states.snapshot().eyeProgress(id).accumulatedMillis());
+            assertTrue(progression.activePlayerIds().isEmpty());
+            assertTrue(notifications.isEmpty());
+        }
+    }
+}

src/test/java/games/dmg/spigotstealth/EyeStatePersistenceTest.java

@@ -0,0 +1,103 @@
+package games.dmg.spigotstealth;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.Map;
+import java.util.UUID;
+import java.util.concurrent.CompletionException;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicBoolean;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+
+class EyeStatePersistenceTest {
+    @TempDir Path directory;
+
+    @Test
+    void yamlRoundTripPreservesEyeAndStealthProgressAndUnknownFields() throws Exception {
+        UUID id = UUID.randomUUID();
+        var repository = new YamlStealthStateRepository(directory.resolve("state.yml"));
+        var eye = new EyeProgress(28_800_123, true, Map.of("future-eye", "keep"));
+        var state = new PersistentStealthState(Map.of(id, PlayerStealthState.empty(id).withProgress(456, true)),
+            Map.of("future-root", "keep")).withEyeProgress(id, eye);
+        repository.save(state);
+        var loaded = repository.load();
+        assertEquals(eye, loaded.eyeProgress(id));
+        assertEquals(state.player(id), loaded.player(id));
+        assertEquals(state.unknownFields(), loaded.unknownFields());
+    }
+
+    @Test
+    void legacyFilesStartAtZeroAndMalformedEyeRecordsCannotGrantUnlocksOrEraseStealth() throws Exception {
+        UUID id = UUID.randomUUID();
+        Path file = directory.resolve("state.yml");
+        var repository = new YamlStealthStateRepository(file);
+        var legacy = new PersistentStealthState(Map.of(id, PlayerStealthState.empty(id).withProgress(456, true)), Map.of());
+        repository.save(legacy);
+        assertEquals(EyeProgress.empty(), repository.load().eyeProgress(id));
+        // Deliberately malformed independent section, not a malformed existing player record.
+        Files.writeString(file, Files.readString(file) + "\neye-progress:\n  " + id
+            + ":\n    accumulated-millis: -1\n    unlocked: true\n");
+        var loaded = repository.load();
+        assertEquals(EyeProgress.empty(), loaded.eyeProgress(id));
+        assertEquals(legacy.player(id), loaded.player(id));
+    }
+
+    @Test
+    void pendingWriteDoesNotExposeDurableUnlockAndSavesOffTheCallingThread() throws Exception {
+        UUID id = UUID.randomUUID();
+        var initial = new PersistentStealthState(Map.of(), Map.of());
+        var entered = new CountDownLatch(1);
+        var release = new CountDownLatch(1);
+        Thread caller = Thread.currentThread();
+        var repository = new StealthStateRepository() {
+            @Override public PersistentStealthState load() { return initial; }
+            @Override public void save(PersistentStealthState state) throws IOException {
+                assertNotEquals(caller, Thread.currentThread());
+                entered.countDown();
+                try {
+                    if (!release.await(5, TimeUnit.SECONDS)) { throw new IOException("test write timeout"); }
+                } catch (InterruptedException exception) {
+                    Thread.currentThread().interrupt();
+                    throw new IOException(exception);
+                }
+            }
+        };
+        var manager = new StealthStateManager(repository, initial);
+        try {
+            var saved = manager.update(state -> state.withEyeProgress(id, new EyeProgress(28_800_000, true)));
+            assertTrue(entered.await(5, TimeUnit.SECONDS));
+            assertTrue(manager.snapshot().eyeProgress(id).unlocked());
+            assertFalse(manager.durableSnapshot().eyeProgress(id).unlocked());
+            release.countDown();
+            saved.join();
+            assertTrue(manager.durableSnapshot().eyeProgress(id).unlocked());
+        } finally { release.countDown(); manager.close(); }
+    }
+
+    @Test
+    void failedWriteCannotGrantDurableUnlockAndSuccessfulRetryCan() {
+        UUID id = UUID.randomUUID();
+        var initial = new PersistentStealthState(Map.of(), Map.of());
+        var fail = new AtomicBoolean(true);
+        var repository = new StealthStateRepository() {
+            @Override public PersistentStealthState load() { return initial; }
+            @Override public void save(PersistentStealthState state) throws IOException {
+                if (fail.get()) { throw new IOException("test disk failure"); }
+            }
+        };
+        var manager = new StealthStateManager(repository, initial);
+        try {
+            assertThrows(CompletionException.class, () -> manager.update(state ->
+                state.withEyeProgress(id, new EyeProgress(28_800_000, true))).join());
+            assertFalse(manager.durableSnapshot().eyeProgress(id).unlocked());
+            fail.set(false);
+            manager.save().join();
+            assertTrue(manager.durableSnapshot().eyeProgress(id).unlocked());
+        } finally { fail.set(false); manager.close(); }
+    }
+}

src/test/java/games/dmg/spigotstealth/IdentityPacketFieldsTest.java

@@ -0,0 +1,32 @@
+package games.dmg.spigotstealth;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import java.util.List;
+import java.util.Optional;
+import java.util.Set;
+import org.junit.jupiter.api.Test;
+
+class IdentityPacketFieldsTest {
+    private final StealthChatMasker masker = new StealthChatMasker(Set.of("Secret"));
+
+    record Entry(String text, Optional<String> tooltip) { }
+    record Bound(int chatType, String name, Optional<String> targetName) { }
+
+    @Test
+    void filtersModernSuggestionEntriesWithoutChangingOrdinaryEntries() throws ReflectiveOperationException {
+        Entry ordinary = new Entry("Someone", Optional.of("help"));
+        List<Entry> entries = List.of(new Entry("sEcReT", Optional.empty()), ordinary);
+        assertEquals(List.of(ordinary), IdentityPacketFields.filterEntries(entries, masker));
+        assertEquals(2, entries.size());
+    }
+
+    @Test
+    void rebuildsDisplayNameRecordWithoutMutatingOriginal() throws ReflectiveOperationException {
+        Bound original = new Bound(42, "Secret", Optional.of("Secret"));
+        Object copy = IdentityPacketFields.mapRecord(original,
+                value -> value.equals("Secret") ? "Anonymous" : value);
+        assertEquals(new Bound(42, "Anonymous", Optional.of("Anonymous")), copy);
+        assertEquals("Secret", original.name());
+    }
+}

src/test/java/games/dmg/spigotstealth/ProtocolLibIdentityMaskingListenerTest.java

@@ -0,0 +1,63 @@
+package games.dmg.spigotstealth;
+
+import static org.junit.jupiter.api.Assertions.*;
+import static org.mockito.Mockito.*;
+
+import com.comphenix.protocol.PacketType;
+import com.comphenix.protocol.events.PacketEvent;
+import com.comphenix.protocol.utility.MinecraftReflection;
+import com.comphenix.protocol.utility.MinecraftVersion;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Set;
+import java.util.concurrent.atomic.AtomicReference;
+import org.bukkit.plugin.Plugin;
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+import org.mockito.MockedStatic;
+
+class ProtocolLibIdentityMaskingListenerTest {
+    private static MockedStatic<MinecraftReflection> reflection;
+
+    @BeforeAll
+    static void initializeProtocolTypesWithoutServer() {
+        MinecraftVersion.setCurrentVersion(new MinecraftVersion(1, 21, 8));
+        reflection = mockStatic(MinecraftReflection.class);
+    }
+
+    @AfterAll
+    static void resetProtocolEnvironment() {
+        reflection.close();
+        MinecraftVersion.setCurrentVersion(null);
+    }
+
+    @Test
+    void skipsPacketWorkWhenNobodyIsConcealed() {
+        AtomicReference<Set<String>> names = new AtomicReference<>(Set.of());
+        var listener = new ProtocolLibIdentityMaskingListener(mock(Plugin.class), names::get, ignored -> { });
+        PacketEvent event = mock(PacketEvent.class);
+        listener.onPacketSending(event);
+        verify(event, never()).getPacket();
+        assertTrue(listener.getSendingWhitelist().getTypes().contains(PacketType.Play.Server.CHAT));
+        assertTrue(listener.getSendingWhitelist().getTypes().contains(PacketType.Play.Server.SYSTEM_CHAT));
+    }
+
+    @Test
+    void readsFreshSnapshotAndWarnsOnceWithoutCancellingOrReplacingFailedPacket() {
+        List<String> warnings = new ArrayList<>();
+        AtomicReference<Set<String>> names = new AtomicReference<>(Set.of());
+        var listener = new ProtocolLibIdentityMaskingListener(mock(Plugin.class), names::get, warnings::add);
+        PacketEvent event = mock(PacketEvent.class);
+        when(event.getPacketType()).thenReturn(PacketType.Play.Server.CHAT);
+        listener.onPacketSending(event);
+        assertTrue(warnings.isEmpty());
+        names.set(Set.of("Secret"));
+        // No real NMS packet: the clone attempt fails and must leave event delivery untouched.
+        listener.onPacketSending(event);
+        listener.onPacketSending(event);
+        assertEquals(1, warnings.size());
+        verify(event, never()).setPacket(any());
+        verify(event, never()).setCancelled(anyBoolean());
+    }
+}

src/test/java/games/dmg/spigotstealth/PurpurDistributionTest.java

@@ -0,0 +1,53 @@
+package games.dmg.spigotstealth;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import java.io.DataInputStream;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.Map;
+import java.util.jar.JarFile;
+import org.junit.jupiter.api.Test;
+import org.yaml.snakeyaml.Yaml;
+
+class PurpurDistributionTest {
+    @Test
+    void packagesNewNameWithoutChangingRuntimeIdentityOrBundlingTheApi() throws Exception {
+        Path artifact = Path.of(System.getProperty("distribution.jar"));
+        String version = System.getProperty("distribution.version");
+        assertEquals("purpur-stealth-" + version + ".jar", artifact.getFileName().toString());
+        try (var jar = new JarFile(artifact.toFile())) {
+            Map<?, ?> metadata = new Yaml().load(jar.getInputStream(jar.getJarEntry("plugin.yml")));
+            assertEquals(version, metadata.get("version"));
+            assertEquals("SpigotStealth", metadata.get("name"), "Retain the data directory and persistent namespace");
+            assertEquals("games.dmg.spigotstealth.SpigotStealthPlugin", metadata.get("main"));
+            assertTrue(((Map<?, ?>) metadata.get("permissions")).containsKey("spigotstealth.admin"));
+            assertFalse(jar.stream().anyMatch(entry -> entry.getName().startsWith("org/bukkit/")
+                || entry.getName().startsWith("org/purpurmc/") || entry.getName().endsWith("Test.class")));
+        }
+    }
+
+    @Test
+    void pluginBytecodeTargetsJava25() throws Exception {
+        try (var jar = new JarFile(System.getProperty("distribution.jar"));
+             var bytecode = new DataInputStream(jar.getInputStream(
+                 jar.getJarEntry("games/dmg/spigotstealth/SpigotStealthPlugin.class")))) {
+            assertEquals(0xCAFEBABE, bytecode.readInt());
+            bytecode.readUnsignedShort();
+            assertEquals(69, bytecode.readUnsignedShort());
+        }
+    }
+
+    @Test
+    void releaseAndCiAgreeWithThePurpurDistributionNameAndToolchain() throws Exception {
+        String build = Files.readString(Path.of("build.gradle.kts"));
+        assertTrue(build.contains("purpur-api:26.2.build.2618-stable"));
+        assertFalse(build.contains("org.spigotmc:spigot-api"));
+        for (String workflow : new String[] {"ci.yml", "release.yml"}) {
+            String content = Files.readString(Path.of(".gitea/workflows", workflow));
+            assertTrue(content.contains("java-version: 25"));
+            assertTrue(content.contains("purpur-stealth-"), workflow);
+            assertFalse(content.contains("spigot-stealth-"), workflow);
+        }
+    }
+}

src/test/java/games/dmg/spigotstealth/ServerListPingListenerTest.java

@@ -0,0 +1,36 @@
+package games.dmg.spigotstealth;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Set;
+import java.util.UUID;
+import org.bukkit.entity.Player;
+import org.bukkit.event.server.ServerListPingEvent;
+import org.junit.jupiter.api.Test;
+
+class ServerListPingListenerTest {
+    @Test
+    void removesOnlyConcealedPlayersFromNativeServerPingSample() {
+        UUID concealedId = UUID.randomUUID();
+        Player visible = player(UUID.randomUUID());
+        Player concealed = player(concealedId);
+        ArrayList<Player> sample = new ArrayList<>(List.of(visible, concealed));
+        ServerListPingEvent event = mock(ServerListPingEvent.class);
+        when(event.iterator()).thenReturn(sample.iterator());
+        ServerListPingListener listener = new ServerListPingListener(() -> Set.of(concealedId));
+
+        listener.onServerListPing(event);
+
+        assertEquals(List.of(visible), sample);
+    }
+
+    private static Player player(UUID playerId) {
+        Player player = mock(Player.class);
+        when(player.getUniqueId()).thenReturn(playerId);
+        return player;
+    }
+}

src/test/java/games/dmg/spigotstealth/ServerPingCompatibilityGuardTest.java

@@ -0,0 +1,24 @@
+package games.dmg.spigotstealth;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+
+import java.util.ArrayList;
+import org.junit.jupiter.api.Test;
+
+class ServerPingCompatibilityGuardTest {
+    @Test
+    void compatibilityFailureLeavesPingHandlingUsableAndWarnsOnlyOnce() {
+        ArrayList<String> warnings = new ArrayList<>();
+        ServerPingCompatibilityGuard guard = new ServerPingCompatibilityGuard(warnings::add);
+
+        assertDoesNotThrow(() -> guard.run(() -> {
+            throw new IllegalArgumentException("unsupported profile representation");
+        }));
+        assertDoesNotThrow(() -> guard.run(() -> {
+            throw new IllegalArgumentException("unsupported profile representation");
+        }));
+
+        assertEquals(1, warnings.size());
+    }
+}

src/test/java/games/dmg/spigotstealth/StealthAdminCommandTest.java

@@ -80,7 +80,10 @@ class StealthAdminCommandTest {
             fixture.command.onCommand(
                     sender, command, "stealthadmin", new String[] {"sleepcount", "include"});
 
-            verify(sender, org.mockito.Mockito.timeout(1000)).sendMessage(contains("now included"));
+            verify(sender, never()).sendMessage(contains("now included"));
+            assertEquals(List.of(), fixture.audit);
+            fixture.runMainThreadCallback();
+            verify(sender).sendMessage(contains("now included"));
             assertEquals(SleepCountPolicy.INCLUDE, fixture.manager.snapshot().sleepCountPolicy());
             verify(fixture.presentation).refreshSleepCountPolicy();
             org.junit.jupiter.api.Assertions.assertTrue(fixture.audit.stream()
@@ -125,7 +128,10 @@ class StealthAdminCommandTest {
         try (Fixture fixture = fixture(playerId)) {
             CommandSender sender = sender(true);
             fixture.command.onCommand(sender, mock(Command.class), "stealthadmin", new String[] {"grant", playerId.toString()});
-            verify(sender, org.mockito.Mockito.timeout(1000)).sendMessage(contains("granted"));
+            verify(sender, never()).sendMessage(contains("granted"));
+            assertEquals(List.of(), fixture.audit);
+            fixture.runMainThreadCallback();
+            verify(sender).sendMessage(contains("granted"));
             org.junit.jupiter.api.Assertions.assertTrue(fixture.manager.snapshot().player(playerId).unlocked());
             org.junit.jupiter.api.Assertions.assertTrue(fixture.audit.stream().anyMatch(message -> message.contains("grant") && message.contains(playerId.toString())));
         }
@@ -167,16 +173,30 @@ class StealthAdminCommandTest {
                 manager, progression, presentation, ignored -> { }, List::of);
         KnownPlayerResolver resolver = new KnownPlayerResolver(manager::snapshot, List::of);
         ArrayList<String> audit = new ArrayList<>();
+        var mainThread = new java.util.concurrent.LinkedBlockingQueue<Runnable>();
         StealthAdminCommand command = new StealthAdminCommand(
-                administration, resolver, Runnable::run, audit::add, Duration.ofHours(8));
+                administration, resolver, mainThread::add, audit::add, Duration.ofHours(8));
-        return new Fixture(manager, command, presentation, audit);
+        return new Fixture(manager, command, presentation, audit, mainThread);
     }
 
     private record Fixture(
             StealthStateManager manager,
             StealthAdminCommand command,
             IdentityPresentation presentation,
-            ArrayList<String> audit) implements AutoCloseable {
+            ArrayList<String> audit,
+            java.util.concurrent.BlockingQueue<Runnable> mainThread) implements AutoCloseable {
+        void runMainThreadCallback() {
+            // A reply is emitted before the audit append. Await and run the whole scheduled callback,
+            // not just the reply invocation, and never read the ArrayList concurrently with the I/O thread.
+            try {
+                Runnable callback = mainThread.poll(5, java.util.concurrent.TimeUnit.SECONDS);
+                org.junit.jupiter.api.Assertions.assertNotNull(callback, "Expected a scheduled main-thread completion");
+                callback.run();
+            } catch (InterruptedException exception) {
+                Thread.currentThread().interrupt();
+                throw new AssertionError("Interrupted waiting for command completion", exception);
+            }
+        }
         @Override public void close() { manager.close(); }
     }
 }

src/test/java/games/dmg/spigotstealth/StealthAdminJoinListenerTest.java

@@ -0,0 +1,83 @@
+package games.dmg.spigotstealth;
+
+import static org.mockito.Mockito.*;
+
+import java.util.List;
+import java.util.Set;
+import java.util.UUID;
+import org.bukkit.entity.Player;
+import org.bukkit.event.player.PlayerJoinEvent;
+import org.junit.jupiter.api.Test;
+
+class StealthAdminJoinListenerTest {
+    @Test
+    void joiningAdminReceivesCountButExistingAdminsDoNotReceiveOrdinaryJoinNotice() {
+        Player joining = player(true);
+        Player existing = player(true);
+        StealthSessionService sessions = sessions(Set.of(UUID.randomUUID(), UUID.randomUUID()));
+        new StealthAdminJoinListener(sessions, () -> List.of(joining, existing)).onJoin(event(joining));
+        verify(joining).sendMessage("[Stealth] 2 players are invisible. Use /stealthadmin list to see who.");
+        verify(existing, never()).sendMessage(anyString());
+    }
+
+    @Test
+    void concealedJoinNotifiesOnlyAdminsWithUpdatedCount() {
+        Player joining = player(false);
+        Player admin = player(true);
+        Player ordinary = player(false);
+        StealthSessionService sessions = sessions(Set.of(joining.getUniqueId()));
+        new StealthAdminJoinListener(sessions, () -> List.of(joining, admin, ordinary)).onJoin(event(joining));
+        verify(admin).sendMessage("[Stealth] An invisible player joined. 1 player is now invisible. Use /stealthadmin list to see who.");
+        verify(joining, never()).sendMessage(anyString());
+        verify(ordinary, never()).sendMessage(anyString());
+    }
+
+    @Test
+    void concealedAdminGetsExactlyOneNoticeEvenWhenIncludedInOnlinePlayers() {
+        Player joining = player(true);
+        Player admin = player(true);
+        StealthSessionService sessions = sessions(Set.of(joining.getUniqueId(), UUID.randomUUID()));
+        new StealthAdminJoinListener(sessions, () -> List.of(joining, admin)).onJoin(event(joining));
+        verify(joining, times(1)).sendMessage("[Stealth] 2 players are invisible. Use /stealthadmin list to see who.");
+        verify(admin).sendMessage("[Stealth] An invisible player joined. 2 players are now invisible. Use /stealthadmin list to see who.");
+    }
+
+    @Test
+    void zeroCountIsSilent() {
+        Player joining = player(true);
+        new StealthAdminJoinListener(sessions(Set.of()), () -> List.of(joining)).onJoin(event(joining));
+        verify(joining, never()).sendMessage(anyString());
+    }
+
+    @Test
+    void ordinaryJoinIsSilentAndSinglePlayerCountUsesSingular() {
+        Player ordinary = player(false);
+        Player admin = player(true);
+        StealthAdminJoinListener listener = new StealthAdminJoinListener(
+                sessions(Set.of(UUID.randomUUID())), () -> List.of(ordinary, admin));
+        listener.onJoin(event(ordinary));
+        verify(ordinary, never()).sendMessage(anyString());
+        verify(admin, never()).sendMessage(anyString());
+        listener.onJoin(event(admin));
+        verify(admin).sendMessage("[Stealth] 1 player is invisible. Use /stealthadmin list to see who.");
+    }
+
+    private static StealthSessionService sessions(Set<UUID> ids) {
+        StealthSessionService sessions = mock(StealthSessionService.class);
+        when(sessions.concealedPlayerIds()).thenReturn(ids);
+        return sessions;
+    }
+
+    private static Player player(boolean admin) {
+        Player player = mock(Player.class);
+        when(player.getUniqueId()).thenReturn(UUID.randomUUID());
+        when(player.hasPermission("spigotstealth.admin")).thenReturn(admin);
+        return player;
+    }
+
+    private static PlayerJoinEvent event(Player player) {
+        PlayerJoinEvent event = mock(PlayerJoinEvent.class);
+        when(event.getPlayer()).thenReturn(player);
+        return event;
+    }
+}

src/test/java/games/dmg/spigotstealth/StealthChatMaskerTest.java

@@ -0,0 +1,70 @@
+package games.dmg.spigotstealth;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import com.google.gson.JsonParser;
+import java.util.Set;
+import org.junit.jupiter.api.Test;
+
+class StealthChatMaskerTest {
+    private final StealthChatMasker masker = new StealthChatMasker(Set.of("Secret"));
+
+    @Test
+    void masksSenderAndRemovesIdentityMetadataWithoutChangingMessage() {
+        String input = """
+                {"translate":"chat.type.text","with":[
+                  {"text":"Secret","hoverEvent":{"action":"show_entity","contents":{"name":"Secret"}},
+                   "clickEvent":{"action":"suggest_command","value":"/msg Secret "}},
+                  {"text":"Secret says hello","clickEvent":{"action":"copy_to_clipboard","value":"Secret"}}]}
+                """;
+        var result = JsonParser.parseString(masker.maskAnnouncement(input)).getAsJsonObject();
+        var args = result.getAsJsonArray("with");
+        assertEquals(JsonParser.parseString("{\"text\":\"Anonymous\",\"obfuscated\":true,\"hoverEvent\":null,\"clickEvent\":null,\"insertion\":\"\"}"), args.get(0));
+        assertEquals(JsonParser.parseString(input).getAsJsonObject().getAsJsonArray("with").get(1), args.get(1));
+    }
+
+    @Test
+    void handlesPrivateMessagesAndAdvancementNamesOnly() {
+        for (String key : Set.of("commands.message.display.incoming", "commands.message.display.outgoing",
+                "chat.type.advancement.task", "chat.type.advancement.goal", "chat.type.advancement.challenge")) {
+            String input = "{\"translate\":\"" + key + "\",\"with\":[\"secret\",{\"text\":\"Secret\"}]}";
+            var args = JsonParser.parseString(masker.maskAnnouncement(input)).getAsJsonObject().getAsJsonArray("with");
+            assertEquals("Anonymous", args.get(0).getAsJsonObject().get("text").getAsString());
+            assertEquals("Secret", args.get(1).getAsJsonObject().get("text").getAsString());
+        }
+    }
+
+    @Test
+    void doesNotTraverseMessageBodyEvenWhenItContainsChatTranslations() {
+        String input = """
+                {"translate":"chat.type.text","with":["Ordinary",
+                  {"translate":"chat.type.text","with":["Secret","body"]}]}
+                """;
+        assertEquals(input, masker.maskAnnouncement(input));
+    }
+
+    @Test
+    void handlesNestedAnnouncementsButNotPlainTextOrUnknownTranslations() {
+        assertTrue(masker.maskAnnouncement("{\"text\":\"\",\"extra\":[{\"translate\":\"chat.type.text\",\"with\":[\"Secret\",\"hello\"]}]}").contains("Anonymous"));
+        for (String input : Set.of("{\"text\":\"Secret: hello\"}", "{\"translate\":\"custom\",\"with\":[\"Secret\"]}", "not json")) {
+            assertEquals(input, masker.maskAnnouncement(input));
+        }
+    }
+
+    @Test
+    void removesInheritedActionsFromArrayParent() {
+        String json = """
+                [{"text":"","hover_event":{"action":"show_text","value":"Secret"}},
+                 {"translate":"chat.type.text","with":["Secret","hello"]}]
+                """;
+        assertFalse(masker.maskAnnouncement(json).contains("Secret"));
+    }
+
+    @Test
+    void recognizesSplitNamesAndMasksWholeNameComponent() {
+        String name = "{\"text\":\"Sec\",\"extra\":[{\"text\":\"ret\"}],\"insertion\":\"Secret\"}";
+        assertTrue(masker.maskDisplayName(name).contains("Anonymous"));
+        assertFalse(masker.maskDisplayName(name).contains("Secret"));
+        assertEquals("\"NotSecret\"", masker.maskDisplayName("\"NotSecret\""));
+    }
+}

src/test/java/games/dmg/spigotstealth/StealthSessionListenerTest.java

@@ -62,8 +62,9 @@ class StealthSessionListenerTest {
             QualifyingInvisibilityService progression = new QualifyingInvisibilityService(
                     manager, Duration.ofHours(8), System::nanoTime, ignored -> { });
             IdentityPresentation presentation = mock(IdentityPresentation.class);
+            StealthSessionService sessions = new StealthSessionService(manager, progression);
             StealthSessionListener listener = new StealthSessionListener(
-                    new StealthSessionService(manager, progression), presentation, "Stealth active");
+                    sessions, presentation, "Stealth active");
             Player player = player(playerId);
             PlayerJoinEvent event = mock(PlayerJoinEvent.class);
             when(event.getPlayer()).thenReturn(player);
@@ -73,6 +74,10 @@ class StealthSessionListenerTest {
             verify(event).setJoinMessage(null);
             verify(presentation).conceal(player);
             verify(player).sendMessage("Stealth active");
+            Player admin = player(UUID.randomUUID());
+            when(admin.hasPermission("spigotstealth.admin")).thenReturn(true);
+            new StealthAdminJoinListener(sessions, () -> java.util.List.of(player, admin)).onJoin(event);
+            verify(admin).sendMessage("[Stealth] An invisible player joined. 1 player is now invisible. Use /stealthadmin list to see who.");
         }
     }
 

src/test/java/games/dmg/spigotstealth/StealthStateShutdownTest.java

@@ -0,0 +1,57 @@
+package games.dmg.spigotstealth;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import java.io.IOException;
+import java.nio.file.Path;
+import java.util.UUID;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.TimeUnit;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+
+class StealthStateShutdownTest {
+    @TempDir Path directory;
+
+    @Test
+    void shutdownReturnsWithoutWaitingForDiskButDrainsTheFinalSnapshotAndRejectsLaterMutations() throws Exception {
+        var disk = new YamlStealthStateRepository(directory.resolve("state.yml"));
+        var saving = new CountDownLatch(1);
+        var release = new CountDownLatch(1);
+        StealthStateRepository repository = new StealthStateRepository() {
+            @Override public PersistentStealthState load() throws IOException { return disk.load(); }
+            @Override public void save(PersistentStealthState state) throws IOException {
+                saving.countDown();
+                try {
+                    if (!release.await(5, TimeUnit.SECONDS)) { throw new IOException("Test disk gate timed out"); }
+                } catch (InterruptedException exception) {
+                    Thread.currentThread().interrupt();
+                    throw new IOException(exception);
+                }
+                disk.save(state);
+            }
+        };
+        var states = new StealthStateManager(repository, repository.load());
+        UUID id = UUID.randomUUID();
+        try {
+            states.update(state -> state.withEyeProgress(id, new EyeProgress(1234, false)));
+            assertTrue(saving.await(3, TimeUnit.SECONDS));
+            // A blocked save must not block the lifecycle caller. The test thread still releases the disk on failure.
+            var closing = CompletableFuture.supplyAsync(states::closeAsync).get(1, TimeUnit.SECONDS);
+            assertFalse(closing.isDone(), "shutdown completion must await the queued durable snapshot");
+            assertSame(closing, states.closeAsync());
+            assertThrows(ExecutionException.class, () -> states.update(state ->
+                    state.withEyeProgress(id, new EyeProgress(28_800_000, true))).get(1, TimeUnit.SECONDS));
+            assertEquals(1234, states.snapshot().eyeProgress(id).accumulatedMillis());
+            release.countDown();
+            closing.get(3, TimeUnit.SECONDS);
+            assertEquals(1234, disk.load().eyeProgress(id).accumulatedMillis());
+            assertEquals(disk.load(), states.durableSnapshot());
+        } finally {
+            release.countDown();
+            states.close();
+        }
+    }
+}