Win conditions

A game ends when an end_game action fires, when countdownSeconds expires, or when a team is eliminated. Here are the common shapes.

Reach a target score

compare fires for anyone over the threshold; a won flag makes it announce once.

- id: win
  when:
    kind: and
    children:
      - { kind: compare, who: any, op: gte, left: { ref: same.state.score }, right: 30 }
      - { kind: state_equals, who: same, key: won, value: false }
  do:
    - { kind: set_state, target: same, key: won, value: true }
    - { kind: send_event, to: any, event: { type: toast, text: "Game over — someone reached 30!" } }
    - { kind: end_game }

Adapted from king_of_the_hill (which announces but, if you want a hard stop, add end_game as shown).

Last one standing

count_state n: 1 holds when exactly one player still matches; bind that survivor and declare them the winner.

- id: winner
  when:
    kind: and
    children:
      - { kind: count_state, who: any, key: alive, value: true, n: 1 }
      - { kind: state_equals, who: same, key: alive, value: true }
  do:
    - { kind: send_event, to: same, event: { type: toast, text: "You win." } }
    - { kind: end_game }

Source: apps/wage-engine/src/games/assassin/game.json (the winner rule; add end_game to stop the session).

Avoid double-announce

count_state/compare re-check every tick. If your do doesn’t itself remove the player from the matching set (e.g. by ending the game), gate it with a wonAnnounced: false flag you flip in the same do, as Bomb Tag does.

Run out the clock

For a fixed-duration game, set the timer at the top level and let the engine end it:

countdownSeconds: 900   # 15 minutes

When it expires the engine ends the game automatically. Decide the winner however you like at that point — Pirate’s Booty compares each crew’s total score.

Team elimination

If every member of a team is out, the engine can end the game on elimination. You typically drive “out” yourself by setting alive: false (see Freeze & thaw and Bots vs Humans’ death rule), then either count_state the survivors or rely on the engine’s elimination check.