[cheyras]

This follows up #357. Everything that pass left on purpose was checked against the Advanced Player's Rulebook v3.4 (2025) and the Play! Pokémon Tournament Rules Handbook. The five items that break the rules now follow them. Decision: decisions/2026/2026-10-19-battle-simulator-turn-timing-and-the-end-of-a-game-follow-the-advanced-player-s.md.

• Tiebreaker game with 6 Prize cards, won by the first player to have fewer Prize cards left (APR "Games can result in a tie"; Tournament Rules 5.8.3.1). This corrects Battle simulator: rules checked against PTCG Live's engine and the official rulings #357's 1-Prize sudden death, which followed older wording.
• "During this turn / your next turn / your opponent's next turn" effects end before Pokémon Checkup, because Checkup is in neither player's turn (APR E-02). "Until the end of your next turn" still applies in it (E-22, E-23).
• Knock Outs from end-of-turn effects are resolved before Checkup. A Knock Out is checked whenever HP becomes zero (APR D), so Checkup healing can no longer save a Pokémon already at 0.
• Setup is face down. Both players' Active and Bench choices stay hidden in hand and go into play together when the game starts (APR G, steps 5–8).
• The turn cap is time being called. The turn is finished, 3 more are played, then the player with fewer Prize cards left wins (reason time). Level, play goes on until one player is ahead (Tournament Rules 5.8.3). Only a long stalemate stays a turn limit draw.

Not changed, because they break no rule: the CPU choosing to go first, and Energy/damage-counter moves written per card.

Verification

• @deckpal/sim: 3,242 tests pass. New rule tests in rules-timing and rules-checklist; each new behavioural test fails with its fix disabled.
• All 36 real PTCG Live games (26 of the owner's logs, which are not committed, plus the 10 fixtures) still replay to the end with matching winners.
• Fuzz: 4,000 random games, 0 failures. The 90 former turn-limit draws now end by time (40) or a tiebreaker game (6).
• deckpal-api test:deck 261, @deckpal/agent-tools 398, and tsc --noEmit across workspaces are clean.
• determinism.test.ts re-pinned: 18 of 40 seeded games change, mostly because setup events are now ordered by the face-down reveal.

🤖 Generated with Claude Code

https://claude.ai/code/session_01MKj6CMZ1kKCNaVjKSHgJpx

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Project	Deployment	Actions	Updated
deckpal	Ready	Preview	Oct 20, 2026 1:39am UTC

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Approved automatically: authored by the repository owner, from a branch in this repo. GitHub forbids self-approval, so this stands in for it (AGENTS.md B12). Required status checks still apply — this does not merge anything.