Reversed, Slow Death heals a point per draw (rules rev 11)

Per the FAQ: a REVERSE riding the cast turns the whole curse — the
victim gains a point for every card drawn, as permanently as the bite.
The stack's reversed verdict now reaches onResolved, and the sustained
effect carries it in its data scratch. Older ledgers attached the
biting curse regardless and replay unchanged (pinned at deckRev 10).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015RCWSTnb1KYTPyL4GmhGnF

packages/engine/test/stones.test.ts

@@ -1,7 +1,8 @@
 import { describe, expect, it } from "vitest";
 import { applyCommand, activePlayer, displays, handLimit, sustainedOn, type GameState, type PlayerId } from "../src/game";
 import type { CardInstance } from "../src/cards";
-import { newGame, must, giveCard, toRound2, faceOff, castAt } from "./helpers";
+import { createGame } from "../src/game";
+import { newGame, must, drain, giveCard, toRound2, faceOff, castAt } from "./helpers";
 
 /** Display a stone for a player during their turn. */
 function displayStone(state: GameState, playerId: PlayerId, stoneId: string, slot = 0): GameState {
@@ -147,6 +148,49 @@ describe("slow death", () => {
     expect(sustainedOn(state, defender, "slow-death").length).toBe(1);
   });
 
+  it("a reverse at the casting turns the curse: a point gained per draw (rev 11)", () => {
+    let { state } = newGame();
+    state = toRound2(state);
+    const { attacker, defender } = faceOff(state);
+    const sd = giveCard(state, attacker, "slow-death");
+    giveCard(state, defender, "reverse", "RV", 0);
+    const r = applyCommand(state, attacker, {
+      type: "cast", instanceId: sd.instanceId, target: { kind: "player", playerId: defender },
+    });
+    if (!r.ok) throw new Error(r.error);
+    state = must(r.state, defender, { type: "counteract", instanceId: "reverse#RV" });
+    state = drain(state);
+    expect(sustainedOn(state, defender, "slow-death").length).toBe(1);
+
+    state = must(state, attacker, { type: "endTurn", draw: 0 });
+    const d = state.players.find((p) => p.id === defender)!;
+    const toDiscard = d.hand.slice(0, 2).map((c) => c.instanceId);
+    state = must(state, defender, { type: "discard", instanceIds: toDiscard });
+    state = must(state, defender, { type: "endTurn", draw: 2 });
+    expect(state.players.find((p) => p.id === defender)!.life).toBe(17);
+  });
+
+  it("older decks attach the biting curse through a reverse (rev ≤10)", () => {
+    let { state } = createGame({ playerIds: ["alice", "bob"], seed: 42, sets: ["basic"], deckRev: 10 });
+    state = toRound2(state);
+    const { attacker, defender } = faceOff(state);
+    const sd = giveCard(state, attacker, "slow-death");
+    giveCard(state, defender, "reverse", "RV", 0);
+    const r = applyCommand(state, attacker, {
+      type: "cast", instanceId: sd.instanceId, target: { kind: "player", playerId: defender },
+    });
+    if (!r.ok) throw new Error(r.error);
+    state = must(r.state, defender, { type: "counteract", instanceId: "reverse#RV" });
+    state = drain(state);
+
+    state = must(state, attacker, { type: "endTurn", draw: 0 });
+    const d = state.players.find((p) => p.id === defender)!;
+    const toDiscard = d.hand.slice(0, 2).map((c) => c.instanceId);
+    state = must(state, defender, { type: "discard", instanceIds: toDiscard });
+    state = must(state, defender, { type: "endTurn", draw: 2 });
+    expect(state.players.find((p) => p.id === defender)!.life).toBe(13);
+  });
+
   it("bloodstone cancels slow death's per-draw point", () => {
     let { state } = newGame();
     state = toRound2(state);