Non-fatal engine panic: AI fallback reached during pending cast (variant PayCost, spell Uro, Titan of…

[Cyrene-RPG]

What happened
briefly describe what you were doing

Diagnostic

Build: v0.42.0 (b902333)
Diagnostic tag: ai-getAction-panic
User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) the-bracket/0.1.0 Chrome/142.0.7444.265 Electron/39.8.10 Safari/537.36

Panic (engine recovered):
panicked at crates\phase-ai\src\search.rs:921:9: AI fallback reached during pending cast (variant PayCost, spell Uro, Titan of Nature's Wrath) — can_cast_object_now has a gap that allowed an uncompletable cast through. Tighten the pre-cast check rather than relying on CancelCast recovery.

[mike-theDude]

Triage analysis

Clarified summary: In build v0.42.0, the AI entered Uro's cast pipeline, reached PayCost with no scored completion, and hit the pending-cast fallback assertion. The engine recovered, but the debug panic ended that AI decision path.

Expected behavior: AI castability checks admit only completable casts; if a gap is encountered, the cast is cancelled without a panic and the game continues consistently across build profiles.

Observed behavior: fallback_action reported variant PayCost, spell Uro, Titan of Nature's Wrath and panicked before recovery.

Oracle text (verified from client/public/card-data.json): “When Uro enters, sacrifice it unless it escaped. Whenever Uro enters or attacks, you gain 3 life and draw a card, then you may put a land card from your hand onto the battlefield. Escape—{G}{G}{U}{U}, Exile five other cards from your graveyard.”

Reproduction status: Current main has targeted evidence of a possible fix: #6969 removed this debug assertion and retained the CancelCast recovery plus an error diagnostic. Runtime confirmation for this PayCost/Uro path is still missing.

Investigation findings: This is AI/casting-flow behavior, not a defect in Uro's parsed card text. #6837 involved the same guard but a different ManaPayment dead end; it is related, not an exact duplicate.

Acceptance criteria: Replaying the affected path on a current build produces no panic in either debug or release. If the error diagnostic still fires, capture the saved state and tighten the pre-cast legality check for the underlying PayCost gap.

[mike-theDude]

Classifier analysis

Verdict: not_card_data_attributable

Matched clause: (none) (supported: n/a)

Reasoning: The report concerns AI fallback behavior during an in-flight cast; Uro's Oracle abilities are represented in card data, and no specific parsed clause is alleged to be unfaithful.

---

Posted by bug-coverage-classifier skill.

[matthewevans]

Closing as shipped. The exact Uro class was fixed in merged #4121 (82889abfb4, fix(engine): deserialize compound EscapeCost from card-data export), now on origin/main and released in v0.49.0 and later. Its integration regression proves: Uro is offered with five other graveyard cards, rejected with four, and the real CastSpell pipeline reaches PayCost::ExileFromZone for exactly five others. Separately, #6969 removed this debug-only fallback assertion, retaining safe CancelCast plus diagnostics. Please reopen with a current-build Uro state if that full pipeline still reaches the diagnostic.