feat(progression): reward unique boss kills

design/log.md

@@ -64,3 +64,9 @@ description: Chronological record of significant Trigger Spawn design decisions.
 - Added a three-second on-screen warm-up cancelled by block movement, jumping, falling, teleportation, world changes, or disconnects.
 - Safe destinations are sampled within the current world's circle using bounded attempts and a closest-elevation search that rejects environmental hazards.
 - Only completed teleports consume cooldown, and incomplete progression receives a post-teleport reminder.
+
+## 2026-08-08 — Progression rewards and reminders
+
+- Successful `/spawn` teleports now identify each remaining boss and show the next permanent boss-based cooldown tier.
+- Fully progressed players receive no unnecessary reminder.
+- Verified that newly credited unique kills make `/spawn` immediately available while duplicate kills preserve the existing cooldown.

design/user-stories/us-008-reward-spawn-progression.md

@@ -2,7 +2,7 @@
 type: User Story
 title: "US-008: Reward and encourage spawn progression"
 description: Remind players how to improve spawn access and reward each newly credited unique boss kill with an immediate cooldown reset.
-status: backlog
+status: done
 ---
 
 # US-008: Reward and encourage spawn progression
@@ -11,15 +11,15 @@ As a **player**, I want `/spawn` to explain how I can improve its cooldown and r
 
 ## Acceptance criteria
 
-- [ ] After every successful `/spawn`, a player who has not defeated all three unique qualifying enemies receives a reminder that defeating the remaining bosses permanently reduces the cooldown.
-- [ ] The reminder identifies the remaining eligible bosses and shows the next cooldown tier.
-- [ ] A player who has completed all three unique qualifying kills does not receive the progression reminder.
-- [ ] Each newly credited unique Warden, Ender Dragon, or Wither kill immediately clears the player's active `/spawn` cooldown.
-- [ ] Clearing the cooldown makes `/spawn` immediately available as a progression reward.
-- [ ] The newly credited kill also permanently applies the improved boss-based cooldown tier.
-- [ ] Repeated kills of an already credited enemy do not clear the cooldown.
-- [ ] The on-screen kill message states that `/spawn` is immediately available and displays the new cooldown tier.
-- [ ] Banned players cannot earn kill credit, a cooldown reset, or an improved tier.
+- [x] After every successful `/spawn`, a player who has not defeated all three unique qualifying enemies receives a reminder that defeating the remaining bosses permanently reduces the cooldown.
+- [x] The reminder identifies the remaining eligible bosses and shows the next cooldown tier.
+- [x] A player who has completed all three unique qualifying kills does not receive the progression reminder.
+- [x] Each newly credited unique Warden, Ender Dragon, or Wither kill immediately clears the player's active `/spawn` cooldown.
+- [x] Clearing the cooldown makes `/spawn` immediately available as a progression reward.
+- [x] The newly credited kill also permanently applies the improved boss-based cooldown tier.
+- [x] Repeated kills of an already credited enemy do not clear the cooldown.
+- [x] The on-screen kill message states that `/spawn` is immediately available and displays the new cooldown tier.
+- [x] Banned players cannot earn kill credit, a cooldown reset, or an improved tier.
 
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