---
type: User Story
title: "US-020: Claim the Tyrant role in the arena"
description: Use the shared one-player arena to replace a Tyrant who was not defeated by another player.
status: done
---

# US-020: Claim the Tyrant role in the arena

As an **opted-in participant**, I want to earn a vacant Tyrant role through the shared boss arena so that environmental death, inactivity, and relinquishment do not assign power randomly.

## Acceptance criteria

- [x] A player directly credited with killing the Tyrant still becomes the new Tyrant immediately without an arena fight.
- [x] Tyrant death without a player killer, Tyrant inactivity, and Tyrant relinquishment end the reign, clear all role-side assignments, and open the shared arena with no active or pending Tyrant.
- [x] The shared arena opens only one role challenge at a time: a vacant Tyrant takes priority, and the Vigilante challenge can open only after a Tyrant becomes active.
- [x] The passive arena boundary uses red particles for an open Tyrant challenge, blue particles for an open Vigilante challenge, and a neutral marker while neither role challenge is open.
- [x] The Tyrant challenge uses the existing configured arena, boss balance, tall visible one-challenger barrier, block-change protection, idle-center boss behavior, containment, reset, notification, and missing-location rules.
- [x] An eligible opted-in participant, including the former Tyrant, may challenge for the vacant Tyrant role; an active Tyrant cannot enter any arena fight.
- [x] Defeating the Tyrant challenge boss assigns the challenger as Tyrant with level zero, no purchases, and exactly one starting unlock choice.
- [x] After winning, the new Tyrant is moved safely outside before any subsequent Vigilante challenge opens.
- [x] Completing the Tyrant challenge immediately permits the blue Vigilante challenge to open at the same location when the Vigilante role is vacant.
- [x] Legacy pending Tyrant replacement state is cleared into an arena vacancy without granting a role.
- [x] Pausing, resetting, restarting, reloading, and repeated or concurrent events cannot duplicate either role boss, challenger, barrier, or assignment.

## Related

- [Transfer and reset the Tyrant role](us-002-transfer-and-reset-tyrant.md)
- [Handle inactivity and arena vacancies](us-010-handle-inactivity-and-selection.md)
- [Claim the Vigilante role in the arena](us-019-claim-vigilante-in-arena.md)
- [Tyrant game state machine](../concepts/game-state-machine.md)