Non-fatal engine panic: completed resumed ChangeZone owns every terminal member outcome: "logical zon…

[pvthicks1101-eng]

What happened
briefly describe what you were doing

Diagnostic

Build: v0.30.0 (51cff6a)
Diagnostic tag: submitAction-panic
User agent: Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/150.0.0.0 Mobile Safari/537.36

Panic (engine recovered):
panicked at crates/engine/src/game/effects/mod.rs:1151:10: completed resumed ChangeZone owns every terminal member outcome: "logical zone-change member 22:3 is not terminal"

[mike-theDude]

Triage analysis

Clarified summary: Build v0.30.0 recovered from an engine panic while completing a resumed ChangeZone effect because logical member 22:3 was still nonterminal when the completion path expected every member to have reached a terminal outcome.

Reproduction status: The diagnostic is specific enough to localize the failing invariant, but the report does not include the gameplay action or a saved state. The current engine source no longer contains this exact assertion text, so the next step is runtime verification on the latest preview. If it recurs, please attach the action being submitted and the saved state immediately before it.

Investigation findings: The panic belongs to resumed multi-member zone-change completion, not the browser submission layer. No exact duplicate was found in open or closed issues.

Likely scope: Engine ChangeZone continuation bookkeeping, particularly the transition from a resumed member outcome to completion of the logical zone-change group.

Acceptance criteria: The same gameplay sequence completes or yields for remaining choices without a panic; no logical member is treated as complete while still nonterminal; and the engine does not silently lose or duplicate a zone-change outcome.

[mcbradd]

Deterministic headless repro + frequency data (pod-lab)

This is the most frequent engine panic in a 2000-game headless AI batch: 17 of 38 aborts land on this exact .expect. Same assertion as #7103, line drift only (:1151 here, :1349 at pin d960fc8b3, :1411 in #7103, :1414 on main @ cbdfa042a).

Re-verified today, which should discharge status:needs-runtime-verify. Seed 92000008 on pin 1b2021e7b (newer than the batch below) aborts with exit 101 in ~8 s solo, twice in a row, and previously in both measurement and interactive execution modes:

thread 'ai-commander-driver' panicked at crates\engine\src\game\effects\mod.rs:1349:10:
completed resumed ChangeZone owns every terminal member outcome: "logical zone-change member 328:3 is not terminal"

Pod: Plunder the Graves (Meren of Clan Nel Toth) / Built From Scratch / Explorers of the Deep / Braaains, --difficulty VeryHard, panic at T21 / 400 actions.

Provenance

pod-lab headless 4-player Commander batch, 2000 games (two candidate decks x 1000), engine pin d960fc8b3, card data f166b930e71c9ccd, K=40 workers, 540 s/game, measurement mode. 38/2000 games (1.9%) exited 101 across 7 distinct assertion sites.

All 17 occurrences

seed	run	tier	T/actions	member	pod (P0 to P3)
92000327	plunder	Medium	T21/400	logical zone-change member 152:3 is not terminal	Mind Flayarrrs, Lightly Armored, Enchantress Rubinia, Meren of Clan Nel Toth
92000381	plunder	Medium	T37/1000	logical zone-change member 81:3 is not terminal	Lightly Armored, Meren of Clan Nel Toth, Heads I Win, Tails You Lose, Most Wanted
92000613	plunder	Hard	T53/1400	logical zone-change member 203:4 is not terminal	Animated Army, Meren of Clan Nel Toth, Built From Scratch, Sliver Swarm
92000913	plunder	Hard	T44/1200	logical zone-change member 304:3 is not terminal	Riveteers Rampage, Meren of Clan Nel Toth, Ahoy Mateys, Scrappy Survivors
92000969	plunder	Medium	T15/200	logical zone-change member 14:3 is not terminal	Lightly Armored, Meren of Clan Nel Toth, Turtle Power!, Temur Roar
92000980	plunder	VeryHard	T41/1000	logical zone-change member 120:3 is not terminal	Meren of Clan Nel Toth, Scrappy Survivors, Masters of Evil, First Flight
93000109	sworn	Hard	T21/400	logical zone-change member 217:3 is not terminal	Timey-Wimey, Ob Nixilis of the Black Oath, Lightly Armored, Seize Control
93000219	sworn	Medium	T31/800	logical zone-change member 223:3 is not terminal	Party Time, Forged In Stone, Lightly Armored, Ob Nixilis of the Black Oath
93000322	sworn	Hard	T42/1200	logical zone-change member 306:9 is not terminal	Blight Curse, Token Triumph, Ob Nixilis of the Black Oath, Lightly Armored
93000396	sworn	Medium	T27/600	logical zone-change member 232:3 is not terminal	Ob Nixilis of the Black Oath, Power Hungry, Lightly Armored, Enduring Enchantments
93000567	sworn	Medium	T16/200	logical zone-change member 262:3 is not terminal	Tony Stark, Reap the Tides, Lightly Armored, Ob Nixilis of the Black Oath
93000627	sworn	Medium	T25/400	logical zone-change member 189:4 is not terminal	Fire Lord Azula, Devour for Power, Y'shtola, Night's Blessed, Ob Nixilis of the Black Oath
93000620	sworn	VeryHard	T33/800	logical zone-change member 190:3 is not terminal	Ob Nixilis of the Black Oath, Scrappy Survivors, Goblin Storm, Plunder the Graves
93000764	sworn	VeryHard	T36/800	logical zone-change member 218:3 is not terminal	Ob Nixilis of the Black Oath, Turtle Power!, Lightly Armored, Mind Seize
93000841	sworn	Hard	T30/800	logical zone-change member 350:3 is not terminal	Arm for Battle, Ob Nixilis of the Black Oath, Blast from the Past, Scrappy Survivors
93000856	sworn	Hard	T59/1200	logical zone-change member 191:4 is not terminal	Ob Nixilis of the Black Oath, Seize Control, Built From Scratch, Forged In Stone
93000896	sworn	VeryHard	T47/1200	logical zone-change member 393:3 is not terminal	Ob Nixilis of the Black Oath, Plunder the Graves, Ahoy Mateys, Lightly Armored

Every failing member is a later sub-member (N:3, N:4, N:9) of a multi-member logical zone change, never N:0. Both candidate decks hit it and the 17 pods share no single deck, so this is not one card.

Repro shape: ai-commander <card-data-dir> --seed <seed> --difficulty <tier> --feed <4-deck-feed.json> (one game per process; panic = exit 101). Full stdout is saved for every one of the 38 panics, and the exact pod feeds are reconstructable from the recorded seat ids - happy to attach one on request.

Other sites from the same batch: #7134 (pending-replacement mana cost, 6x), #7135 (buried reveal continuation, 2x), #6867 (paused-child continuation, 7x), #6822 / #7052 (draw bookkeeping, 5x), #6706 (exile-play ledger, 1x).

Evidence only - no fix attempted.

Claude Code