From e30f3f0903d688180d5635c7a10f95c70a10b845 Mon Sep 17 00:00:00 2001
From: Eric Wagoner <ewagoner@gmail.com>
Date: Thu, 20 Aug 2026 21:21:00 -0400
Subject: [PATCH] The automaton guards gold only within sight (X2XN stall)

The guard-the-gold rung cast SAFE/GLUE at a floor treasure with no
line-of-sight check; the engine refused the cast and the fallback
burned the bot's whole turn.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---
 packages/engine/src/automaton.ts       |  6 ++-
 packages/engine/test/automaton.test.ts | 55 +++++++++++++++++++++++++-
 2 files changed, 58 insertions(+), 3 deletions(-)

diff --git a/packages/engine/src/automaton.ts b/packages/engine/src/automaton.ts
index 7097216..04c4a12 100644
--- a/packages/engine/src/automaton.ts
+++ b/packages/engine/src/automaton.ts
@@ -1034,9 +1034,11 @@ function selfCare(view: GameView, style: AutomatonStyle, tier: TierTraits): Comm
   const myFloorTreasure = tier.guardGold
     ? view.treasures.find((t) => t.owner === view.you && t.position && !t.carriedBy)
     : undefined;
-  if (myFloorTreasure && enemyNear) {
+  // Both spells demand line of sight to the gold; a blind cast would be
+  // refused and cost the whole turn.
+  if (myFloorTreasure && enemyNear && sightedCellsFor(view).has(cellKey(myFloorTreasure.position!))) {
     const safe = inHand(view, "safe");
-    if (safe) {
+    if (safe && !view.squareContents[cellKey(myFloorTreasure.position!)]) {
       return { type: "cast", instanceId: safe.instanceId, target: { kind: "cell", cell: myFloorTreasure.position! } };
     }
     const glue = inHand(view, "glue");
diff --git a/packages/engine/test/automaton.test.ts b/packages/engine/test/automaton.test.ts
index 65a51e9..8c81e0e 100644
--- a/packages/engine/test/automaton.test.ts
+++ b/packages/engine/test/automaton.test.ts
@@ -6,7 +6,7 @@ import {
   type PlayerId,
 } from "../src/game";
 import { cellKey, edgeKey } from "../src/board";
-import { viewFor } from "../src/view";
+import { sightedCellsFor, viewFor } from "../src/view";
 import { automatonCommand, automatonFallback, type AutomatonStyle, type AutomatonTier } from "../src/automaton";
 
 /** Whose input does the maze want right now? */
@@ -170,6 +170,59 @@ describe("the clockwork does not waste counters on pointless targets", () => {
   });
 });
 
+describe("the clockwork guards gold only within sight", () => {
+  // Game X2XN: the bot blind-cast SAFE at a treasure it could not see, the
+  // engine refused it, and the fallback burned the whole turn.
+  function goldOnTheFloor() {
+    let { state } = createGame({ playerIds: ["bot", "foe"], seed: 7, sets: ["basic", "expansion1"], deckRev: 36 });
+    while (actingSeat(state) !== "bot") {
+      const r = applyCommand(state, actingSeat(state), { type: "endTurn", draw: 0 });
+      if (!r.ok) throw new Error(r.error);
+      state = r.state;
+    }
+    const bot = state.players.find((p) => p.id === "bot")!;
+    const foe = state.players.find((p) => p.id === "foe")!;
+    foe.position = { ...bot.position };
+    bot.hand = [{ instanceId: "safe#T", cardId: "safe" }];
+    const gold = state.treasures.find((t) => t.owner === "bot")!;
+    gold.carriedBy = null;
+    return { state, bot, gold };
+  }
+
+  it("never blind-casts SAFE at a treasure out of sight", () => {
+    const { state, bot, gold } = goldOnTheFloor();
+    const sighted = sightedCellsFor(viewFor(state, "bot"));
+    const hidden = Object.keys(state.board.cells).find(
+      (k) => !sighted.has(k) && !state.squareContents[k],
+    )!;
+    const [x, y] = hidden.split(",").map(Number);
+    gold.position = { x: x!, y: y! };
+
+    const cmd = automatonCommand(viewFor(state, "bot"), "hunter", "archmage");
+    // Whatever the brain picks, the engine must accept it — a refusal
+    // forfeits the bot's turn.
+    const chosen = cmd ?? automatonFallback(viewFor(state, "bot"), "archmage");
+    expect(applyCommand(state, "bot", chosen).ok).toBe(true);
+  });
+
+  it("still locks up gold it can see", () => {
+    const { state, bot, gold } = goldOnTheFloor();
+    const sighted = sightedCellsFor(viewFor(state, "bot"));
+    const seen = [...sighted].find(
+      (k) => k !== cellKey(bot.position) && !state.squareContents[k],
+    )!;
+    const [x, y] = seen.split(",").map(Number);
+    gold.position = { x: x!, y: y! };
+
+    const cmd = automatonCommand(viewFor(state, "bot"), "hunter", "archmage");
+    expect(cmd).toEqual({
+      type: "cast", instanceId: "safe#T",
+      target: { kind: "cell", cell: gold.position },
+    });
+    expect(applyCommand(state, "bot", cmd!).ok).toBe(true);
+  });
+});
+
 describe("a clogged hand gets shed, not hoarded", () => {
   it("the bot discards dead weight so the end-of-turn draw has room", () => {
     let { state } = createGame({ playerIds: ["bot", "other"], seed: 42, sets: ["basic"], deckRev: 13 });