Nissa, Steward of Elements bug — AI cast Nissa for X=0, it entered with 0 loyalty but remained on the battlefield inste…

[matthewevans]

Reported in Discord: https://discord.com/channels/1485498006781427802/1518577679308423168/1518577679308423168

Thread: Nissa, Steward of Elements bug
Cards: none detected
Parser status: has_gaps
Extraction confidence: 0.90

Summary

AI cast Nissa for X=0, it entered with 0 loyalty but remained on the battlefield instead of dying to SBAs

Oracle text (verified from client/public/card-data.json)

No card names were detected for this report.

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_{report_id: discord:1518577679308423168:1518577679308423168:0 · discord: 1518577679308423168/1518577679308423168}

[mike-theDude]

Card identified as Nissa, Steward of Elements (mana cost {X}{G}{U}, printed loyalty X). Its own bundled ruling states plainly: "If X is 0, Nissa enters the battlefield with no loyalty and is put into her owner's graveyard before you can activate her abilities" — exactly the behavior the report says is missing. Root cause traced in the engine: apply_card_face_to_object (crates/engine/src/game/printed_cards.rs) parses the printed loyalty field via value.parse::<u32>().ok(), so a literal "X" loyalty fails to parse and obj.loyalty/obj.base_loyalty become None rather than being resolved from the chosen X (obj.cost_x_paid, which the engine already tracks and threads through for other X-based ETB effects like Ravenous). intrinsic_face_counters then only seeds a CounterType::Loyalty counter if loy > 0, i.e. it's skipped both when loyalty is None (always, for Nissa) and — even if it were wired — when X is 0. Because no Loyalty counter is ever placed, the CR 704.5i zero-loyalty SBA (check_zero_loyalty in sba.rs, which checks obj.loyalty.is_some_and(|l| l == 0)) never matches None, so Nissa never dies to it regardless of X. This is a genuine engine gap for X-loyalty planeswalkers (the entering-loyalty-from-X path was never wired up), not merely an X=0 edge case.

status:confirmed, classifier:unsupported-aspect

[mike-theDude]

PR #6637 (e50ae6b) fixed this exact Nissa X-loyalty issue. The engine now preserves typed PrintedLoyalty::X, threads the announced X through stack resolution into entry counters, and retains a real base loyalty of 0 when X=0 so the existing zero-loyalty planeswalker state-based action moves Nissa to the graveyard. The PR adds an exact Nissa integration test for X loyalty entry. Could a maintainer close or delete this stale issue?