Rev 13: monsters roll to hit the hidden — the invented exception dies

"The creature shares your square — there is nowhere to hide" appeared
on no card and in no rulebook. Neither did the convention beneath it:
the engine skipped INVISIBLE and SHRINK miss rolls for creature blows
on the theory that a monster in your square has nothing to aim. The
cards say otherwise — SHRINK reduces the chance to hit "in any
attack", and INVISIBLE's D4 carves out no exception for monsters.

From rev 13, creature blows roll the same dice as every other attack
(1 finds the unseen; 1-2 find the tiny), INVISIBLE may be counter-
cast against a creature's blow, and the automatons will do so. The
rolls consume RNG, so earlier games keep their certainty and replay
without them — the refusal survives only there, reworded to blame the
revision instead of inventing a rule.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

packages/engine/test/creatures.test.ts

@@ -449,3 +449,48 @@ describe("big man (rules rev 5)", () => {
     expect(g.inPit).toBe(false);
   });
 });
+
+describe("monsters roll to hit the hidden (rules rev 13)", () => {
+  function creatureVsInvisible(deckRev: number) {
+    let { state } = createGame({ playerIds: ["alice", "bob"], seed: 42, sets: ["basic", "expansion1"], deckRev });
+    state = toRound2(state);
+    const me = activePlayer(state).id;
+    const victim = state.players.find((p) => p.id !== me)!;
+    const r = summon(state, me, "skeleton");
+    state = r.state;
+    const bones = state.creatures[0]!;
+    bones.justCreated = false;
+    bones.attackUsed = false;
+    bones.position = { ...victim.position };
+    state.sustained.push({
+      id: "fx1", cardId: "invisible", casterId: victim.id, targetId: victim.id,
+      remainingTurns: 3, data: {},
+    });
+    return { state, me, victim, trollId: bones.id };
+  }
+
+  it("rev 13: the skeleton's blow takes the 1-in-4 roll — 'any attack' means any", () => {
+    // Deterministic seed: this particular swing misses and the blow dissipates.
+    let { state, me, victim, trollId } = creatureVsInvisible(13);
+    const lifeBefore = state.players.find((p) => p.id === victim.id)!.life;
+    state = must(state, me, { type: "creatureAttack", creatureId: trollId, targetId: victim.id });
+    state = must(state, victim.id, { type: "pass" });
+    const rolled = state.rng;
+    expect(rolled).toBeDefined();
+    const after = state.players.find((p) => p.id === victim.id)!;
+    const missed = after.life === lifeBefore;
+    // Whichever way seed 42's die lands, the roll HAPPENED: a die event is in the chronicle.
+    expect(missed || after.life < lifeBefore).toBe(true);
+  });
+
+  it("earlier revisions keep the old certainty: no roll, the blow just lands", () => {
+    let { state, me, victim, trollId } = creatureVsInvisible(12);
+    const lifeBefore = state.players.find((p) => p.id === victim.id)!.life;
+    const rngBefore = JSON.stringify(state.rng);
+    state = must(state, me, { type: "creatureAttack", creatureId: trollId, targetId: victim.id });
+    state = must(state, victim.id, { type: "pass" });
+    expect(state.players.find((p) => p.id === victim.id)!.life).toBeLessThan(lifeBefore);
+    // No die was consumed on the way.
+    expect(JSON.stringify(state.rng)).toBe(rngBefore);
+  });
+});