Cards whose turned-face-up triggered ability is templated with "As ~ is turned face up, [effect]" (rather than "When …") are unsupported — the clause falls through to an Unimplemented effect: Hooded Hydra (put five +1/+1 counters), Bubble Smuggler (put four +1/+1 counters), Gift of Doom (may attach it to a creature), Crowd-Control Warden.
The trigger classifier (has_trigger_prefix) only accepts when/whenever/at, so the "As"-led line is routed to effect parsing. The engine already models TriggerMode::TurnFaceUp and fires it at runtime on GameEvent::TurnedFaceUp (trigger_matchers.rs), and the "When ~ is turned face up" form already parses — only the "As" templating (CR 711 megamorph/disguise + CR 603.3) is missing.
Fix: recognize the "As" lead, scoped to the "is turned face up" phrase (so "As ~ enters" replacements are untouched) — has_trigger_prefix admits it and the trigger core rewrites the lead to the canonical "When " before parsing.
Local regen: 4 cards flip to supported, 0 regressions; full engine lib suite green.
Cards whose turned-face-up triggered ability is templated with "As ~ is turned face up, [effect]" (rather than "When …") are unsupported — the clause falls through to an Unimplemented effect: Hooded Hydra (put five +1/+1 counters), Bubble Smuggler (put four +1/+1 counters), Gift of Doom (may attach it to a creature), Crowd-Control Warden.
The trigger classifier (
has_trigger_prefix) only acceptswhen/whenever/at, so the "As"-led line is routed to effect parsing. The engine already modelsTriggerMode::TurnFaceUpand fires it at runtime onGameEvent::TurnedFaceUp(trigger_matchers.rs), and the "When ~ is turned face up" form already parses — only the "As" templating (CR 711 megamorph/disguise + CR 603.3) is missing.Fix: recognize the "As" lead, scoped to the "is turned face up" phrase (so "As ~ enters" replacements are untouched) —
has_trigger_prefixadmits it and the trigger core rewrites the lead to the canonical "When " before parsing.Local regen: 4 cards flip to supported, 0 regressions; full engine lib suite green.