ADD joins two number cards on movement, as printed

"You may add two NUMBER cards together for any single action" —
movement included. The engine accepts a second movement number when an
ADD accompanies it (once per turn); the client spends your Add
automatically and says so on the button. 120 tests passing.

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

packages/engine/src/game.ts

@@ -133,6 +133,8 @@ export interface TurnState {
   secondAttackUsed: boolean;
   /** Wand instances already used this turn ("maximum of once per turn"). */
   wandsUsed: string[];
+  /** ADD spent to allow a second movement number card this turn. */
+  movementAddUsed: boolean;
   /** SLOW: "his attacks [reduce] to every other turn". */
   attackForbidden: boolean;
   actionsEnded: boolean;
@@ -525,7 +527,7 @@ export type CastTarget =
 
 export type Command =
   | { type: "move"; direction: Side }
-  | { type: "playNumberForMovement"; instanceId: string }
+  | { type: "playNumberForMovement"; instanceId: string; addInstanceId?: string }
   | { type: "punch"; targetId: PlayerId }
   | { type: "warpStep" }
   | { type: "moveCreature"; creatureId: string; direction: Side }
@@ -2948,6 +2950,7 @@ export function createGame(config: GameConfig): { state: GameState; events: Game
       attackUsed: false,
       secondAttackUsed: false,
       wandsUsed: [],
+      movementAddUsed: false,
       attackForbidden: false,
       actionsEnded: false,
     },
@@ -3062,7 +3065,7 @@ export function applyCommand(state: GameState, playerId: PlayerId, command: Comm
 
   switch (command.type) {
     case "move": return doMove(state, command.direction);
-    case "playNumberForMovement": return doPlayNumberForMovement(state, command.instanceId);
+    case "playNumberForMovement": return doPlayNumberForMovement(state, command.instanceId, command.addInstanceId);
     case "punch": return doPunch(state, command.targetId);
     case "warpStep": return doWarpStep(state);
     case "moveCreature": return doMoveCreature(state, command.creatureId, command.direction);
@@ -3378,17 +3381,29 @@ function doWarpStep(prev: GameState): CommandResult {
   return { ok: true, state, events: [{ type: "warpStepped", player: p.id, from, to: p.position }] };
 }
 
-function doPlayNumberForMovement(prev: GameState, instanceId: string): CommandResult {
+function doPlayNumberForMovement(prev: GameState, instanceId: string, addInstanceId?: string): CommandResult {
   const blocked = requireActionsAvailable(prev);
   if (blocked) return err(blocked);
-  if (prev.turn.numberPlayedForMovement) return err("only one number card may boost movement per turn");
   const mover = activePlayer(prev);
   if (sustainedOn(prev, mover.id, "slow").length > 0) {
     return err("you are slowed — no number cards for movement");
   }
+  // "You may add two NUMBER cards together for any single action" — an ADD
+  // permits one extra movement number this turn.
+  if (prev.turn.numberPlayedForMovement) {
+    if (!addInstanceId) return err("only one number card may boost movement per turn (ADD permits a second)");
+    if (prev.turn.movementAddUsed) return err("ADD already joined two numbers to your movement");
+  }
 
   const state = clone(prev);
   const p = activePlayer(state);
+  if (state.turn.numberPlayedForMovement && addInstanceId) {
+    const addCard = p.hand.find((c) => c.instanceId === addInstanceId);
+    if (!addCard || addCard.cardId !== "add") return err("ADD card not in hand");
+    takeFromHand(p, addInstanceId);
+    state.discard.push(addCard);
+    state.turn.movementAddUsed = true;
+  }
   const card = takeFromHand(p, instanceId);
   if (!card) return err("card not in hand");
   if (!isNumberCard(card.cardId)) return err("not a number card");
@@ -4604,6 +4619,7 @@ function beginTurnFor(state: GameState, events: GameEvent[], index: number): voi
     attackUsed: false,
     secondAttackUsed: false,
     wandsUsed: [],
+    movementAddUsed: false,
     attackForbidden,
     actionsEnded: false,
   };

packages/engine/test/expansion-combat.test.ts

@@ -246,3 +246,23 @@ describe("thumb of god (divine meteor)", () => {
     expect(allObjects.some((c) => c.cardId === "dagger")).toBe(true);
   });
 });
+
+describe("add for movement", () => {
+  it("an ADD permits a second number card on movement, once", () => {
+    let { state } = newGame();
+    const me = activePlayer(state).id;
+    giveCard(state, me, "number-3", "N1", 0);
+    giveCard(state, me, "number-2", "N2", 1);
+    giveCard(state, me, "add", "A", 2);
+    giveCard(state, me, "number-4", "N3", 3);
+    state = must(state, me, { type: "playNumberForMovement", instanceId: "number-3#N1" });
+    expect(state.turn.movementAllowance).toBe(6);
+    // Second without ADD: refused.
+    expect(applyCommand(state, me, { type: "playNumberForMovement", instanceId: "number-2#N2" }).ok).toBe(false);
+    // With ADD: allowed.
+    state = must(state, me, { type: "playNumberForMovement", instanceId: "number-2#N2", addInstanceId: "add#A" });
+    expect(state.turn.movementAllowance).toBe(8);
+    // A third is refused even with another add wished for.
+    expect(applyCommand(state, me, { type: "playNumberForMovement", instanceId: "number-4#N3" }).ok).toBe(false);
+  });
+});