The Alter Ego casts from its own square; the first-stride cue leaves the maze

Randy raised his double, selected it, and could cast nothing through
it: the card's whole point — "it may use any of the spells in your
hand, and you need not be in its L.O.S." — had never been wired. A
cast may now name the double, and the double's square becomes the
spell's origin: sight, reach, the launch point the reel films, and
the direction a knockback or rout pushes. The hand, the attack, and
every answer to it stay the caster's. Spells that move the caster's
own body — a goat's charge, a swap — do not travel through it. On the
board, the double's sight lights the eligible squares; selecting the
double and then a card aims from where it stands. A test hides the
caster and fires through the double.

The first-stride caption sat on the maze and hid the walls beside the
wizard; it now stands above the board with a color chip for "you."

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Jm2auWk6RP71CjaAb4FMoG

packages/engine/src/game.ts

@@ -212,6 +212,9 @@ export interface CastStack {
   reflectedBase?: { damage: number; duration: number };
   /** The wraith's touch also steals a random card if damage lands. */
   creatureTouch?: "wraith" | "claw";
+  /** Where the spell left from when not the attacker's own square: an
+   * ALTER EGO's. Knockbacks and routs push away from here. */
+  origin?: Cell;
   /** A spell freed from slime: counteractions cannot touch its caster. */
   trapped?: boolean;
   /** STRENGTH's tear: "this would be an attack" — the grab rides the stack
@@ -836,6 +839,10 @@ export type Command =
       powerAttackPoints?: number;
       target?: CastTarget;
       params?: CastParams;
+      /** ALTER EGO: the double's creature id, when the spell leaves from
+       * its square — "it may use any of the spells in your hand, and you
+       * need not be in its L.O.S. to do so." */
+      via?: string;
     }
   | { type: "setAmbush"; instanceId: string; trigger: AmbushTrigger; spellInstanceId: string; numberInstanceIds?: string[]; cell?: Cell }
   | { type: "cancelAmbush"; ambushId: string }
@@ -903,6 +910,8 @@ interface Magnitude {
 }
 
 interface ResolutionContext {
+  /** The square the blow came from: the attacker's, or their double's. */
+  origin: Cell;
   state: GameState;
   events: GameEvent[];
   attacker: PlayerState;
@@ -1069,7 +1078,7 @@ const CARD_EFFECTS: Record<string, AttackEffect | NeutralEffect | CounterEffect>
     onResolved: (ctx) => {
       const knock = ctx.stack.params?.knockback ?? 0;
       if (knock <= 0 || ctx.fullyStopped || !ctx.defender.alive) return;
-      knockBack(ctx.state, ctx.events, ctx.attacker, ctx.defender, knock);
+      knockBack(ctx.state, ctx.events, ctx.attacker, ctx.defender, knock, ctx.origin);
     },
   },
   "sudden-death": { kind: "attack", requiresLos: true, baseDamage: () => 10 },
@@ -1114,7 +1123,7 @@ const CARD_EFFECTS: Record<string, AttackEffect | NeutralEffect | CounterEffect>
     onResolved: (ctx) => {
       if (ctx.fullyStopped || !ctx.defender.alive) return;
       const n = ctx.stack.numberValue ?? 1;
-      goAwayRout(ctx.state, ctx.events, ctx.attacker, ctx.defender, n);
+      goAwayRout(ctx.state, ctx.events, ctx.attacker, ctx.defender, n, ctx.origin);
       ctx.defender.lostTurns++;
       ctx.events.push({ type: "stunned", player: ctx.defender.id, turnsLost: 1 });
     },
@@ -5243,6 +5252,19 @@ function doCast(prev: GameState, cmd: Extract<Command, { type: "cast" }>): Comma
   const inHand = caster.hand.find((c) => c.instanceId === cmd.instanceId);
   if (!inHand) return err("card not in hand");
   const def = cardDef(inHand.cardId);
+  // ALTER EGO: "It may use any of the spells in your hand, and you need
+  // not be in its L.O.S. to do so." The double's square is where the
+  // spell leaves from — sight, reach, and the blow's direction are its —
+  // while the hand, the attack, and any answer to it stay the caster's.
+  // Spells that move the caster's own body do not travel through it.
+  let origin: Cell = caster.position;
+  if (cmd.via) {
+    const ego = state.creatures.find((c) => c.id === cmd.via);
+    if (!ego || ego.kind !== "alter-ego" || ego.controllerId !== caster.id) return err("that is not your double");
+    if (!cmd.target) return err("your double casts only at a target");
+    if (inHand.cardId === "butt-head" || inHand.cardId === "swap") return err(`${def.name} moves your own body — not your double's to cast`);
+    origin = ego.position;
+  }
   const effect = CARD_EFFECTS[inHand.cardId];
   if (!effect) return err(`${def.name} is not implemented yet`);
   if (effect.kind === "counter") {
@@ -5328,7 +5350,7 @@ function doCast(prev: GameState, cmd: Extract<Command, { type: "cast" }>): Comma
     const events: GameEvent[] = [{
       type: "spellCast", caster: caster.id, card: inHand, cardId: inHand.cardId,
       numberCards: mods.numbers, numberValue: mods.magnitude.numberValue,
-      from: caster.position, target: null, targetCell: null,
+      from: origin, target: null, targetCell: null,
     }];
     attachSustained(state, events, "disease", caster.id, caster.id, mods.magnitude.duration);
     return { ok: true, state, events };
@@ -5342,12 +5364,12 @@ function doCast(prev: GameState, cmd: Extract<Command, { type: "cast" }>): Comma
     if (cmd.target?.kind === "creature") {
       const creature = state.creatures.find((c) => c.id === (cmd.target as { creatureId: string }).creatureId);
       if (!creature) return err("no such creature");
-      if (effect.sameSquare && cellKey(creature.position) !== cellKey(caster.position)) {
+      if (effect.sameSquare && cellKey(creature.position) !== cellKey(origin)) {
         return err("you must be in the same square");
       }
       if (effect.requiresLos && !(mods.aroundCorner
-        ? bentLos(state, caster, caster.position, creature.position)
+        ? bentLos(state, caster, origin, creature.position)
-        : casterLos(state, caster, caster.position, creature.position))) {
+        : casterLos(state, caster, origin, creature.position))) {
         return err("no line of sight to the creature");
       }
       const wandEvents: GameEvent[] = [];
@@ -5362,7 +5384,7 @@ function doCast(prev: GameState, cmd: Extract<Command, { type: "cast" }>): Comma
       const events: GameEvent[] = [...wandEvents, {
         type: "spellCast", caster: caster.id, card: inHand, cardId: inHand.cardId,
         numberCards: mods.numbers, numberValue: mods.magnitude.numberValue,
-        from: caster.position, target: null, targetCell: creature.position,
+        from: origin, target: null, targetCell: creature.position,
       }];
       // "Any WATERBOLT or WATERWALL will destroy it" (FIRE IMP).
       if (creature.kind === "fire-imp" && inHand.cardId === "waterbolt") {
@@ -5383,7 +5405,7 @@ function doCast(prev: GameState, cmd: Extract<Command, { type: "cast" }>): Comma
     if (cmd.target?.kind === "cell" &&
         state.squareContents[cellKey(cmd.target.cell)]?.kind === "safe") {
       const cell = cmd.target.cell;
-      if (effect.sameSquare && cellKey(cell) !== cellKey(caster.position)) {
+      if (effect.sameSquare && cellKey(cell) !== cellKey(origin)) {
         return err("you must be in the same square");
       }
       // castSight carries the whole sight law: straight lines, the
@@ -5405,7 +5427,7 @@ function doCast(prev: GameState, cmd: Extract<Command, { type: "cast" }>): Comma
       const events: GameEvent[] = [...wandEvents, {
         type: "spellCast", caster: caster.id, card: inHand, cardId: inHand.cardId,
         numberCards: mods.numbers, numberValue: mods.magnitude.numberValue,
-        from: caster.position, target: null, targetCell: { ...cell },
+        from: origin, target: null, targetCell: { ...cell },
       }];
       const box = state.squareContents[cellKey(cell)]!;
       box.damage += dmg;
@@ -5424,8 +5446,8 @@ function doCast(prev: GameState, cmd: Extract<Command, { type: "cast" }>): Comma
         state.squareContents[cellKey(cmd.target.cell)]?.kind === "slime") {
       const cell = cmd.target.cell;
       if (effect.requiresLos && !(mods.aroundCorner
-        ? bentLos(state, caster, caster.position, cell)
+        ? bentLos(state, caster, origin, cell)
-        : casterLos(state, caster, caster.position, cell))) {
+        : casterLos(state, caster, origin, cell))) {
         return err("no line of sight to the slime");
       }
       const wandEvents: GameEvent[] = [];
@@ -5469,7 +5491,7 @@ function doCast(prev: GameState, cmd: Extract<Command, { type: "cast" }>): Comma
       if (current !== "wall" && current !== "door") {
         return err("there is no wall or door on that edge to attack");
       }
-      if (effect.sameSquare && !touchesEdge(caster.position, cell, side)) {
+      if (effect.sameSquare && !touchesEdge(origin, cell, side)) {
         return err("you must stand beside the wall");
       }
       if (effect.requiresLos && !castSightEdge(state, caster, cmd, view, cell, side)) {
@@ -5495,7 +5517,7 @@ function doCast(prev: GameState, cmd: Extract<Command, { type: "cast" }>): Comma
       const events2: GameEvent[] = [...wandEvents, {
         type: "spellCast", caster: caster.id, card: inHand, cardId: inHand.cardId,
         numberCards: mods.numbers, numberValue: mods.magnitude.numberValue,
-        from: caster.position, target: null, targetCell: cell,
+        from: origin, target: null, targetCell: cell,
       }];
       const problem = damageWall(state, events2, caster, cell, side, dmg, inHand.cardId);
       if (problem) return err(problem);
@@ -5524,7 +5546,7 @@ function doCast(prev: GameState, cmd: Extract<Command, { type: "cast" }>): Comma
       const events: GameEvent[] = [{
         type: "spellCast", caster: caster.id, card: inHand, cardId: inHand.cardId,
         numberCards: mods.numbers, numberValue: mods.magnitude.numberValue,
-        from: caster.position, target: null, targetCell: null,
+        from: origin, target: null, targetCell: null,
       }];
       const queue = turnOrderFrom(state, caster.id).filter((id) =>
         id !== caster.id && state.players.find((p) => p.id === id)!.alive);
@@ -5536,7 +5558,7 @@ function doCast(prev: GameState, cmd: Extract<Command, { type: "cast" }>): Comma
     if (cmd.target.playerId === caster.id) return err("you cannot attack yourself");
     const target = state.players.find((p) => p.id === (cmd.target as { playerId: PlayerId }).playerId);
     if (!target || !target.alive) return err("no such living player");
-    if (effect.sameSquare && cellKey(target.position) !== cellKey(caster.position)) {
+    if (effect.sameSquare && cellKey(target.position) !== cellKey(origin)) {
       return err("you must be in the same square");
     }
     const statusBlock = attackBlockedByStatus(state, caster, target);
@@ -5544,8 +5566,8 @@ function doCast(prev: GameState, cmd: Extract<Command, { type: "cast" }>): Comma
     const preEvents: GameEvent[] = [];
     if (effect.requiresLos) {
       const sighted = mods.aroundCorner
-        ? bentLos(state, caster, caster.position, target.position)
+        ? bentLos(state, caster, origin, target.position)
-        : casterLos(state, caster, caster.position, target.position);
+        : casterLos(state, caster, origin, target.position);
       if (!sighted) return err("no line of sight to the target");
     }
     // Attacking someone breaks any BUDDY pact you swore to them.
@@ -5579,9 +5601,9 @@ function doCast(prev: GameState, cmd: Extract<Command, { type: "cast" }>): Comma
     // go intended distance" — if the die disagrees with the true direction,
     // the spell hits whoever lies that way, or dissipates.
     if (isBlinded(state, caster) &&
-        cellKey(target.position) !== cellKey(caster.position)) {
+        cellKey(target.position) !== cellKey(origin)) {
-      const dx = target.position.x - caster.position.x;
+      const dx = target.position.x - origin.x;
-      const dy = target.position.y - caster.position.y;
+      const dy = target.position.y - origin.y;
       const intended: Side =
         Math.abs(dx) >= Math.abs(dy) && dx !== 0 ? (dx > 0 ? "E" : "W") : dy > 0 ? "S" : "N";
       const [roll, rngNext] = rollDie(state.rng);
@@ -5590,11 +5612,11 @@ function doCast(prev: GameState, cmd: Extract<Command, { type: "cast" }>): Comma
       if (rolled !== intended) {
         const along = state.players.find((p) => {
           if (!p.alive || p.id === caster.id) return false;
-          const px = p.position.x - caster.position.x;
+          const px = p.position.x - origin.x;
-          const py = p.position.y - caster.position.y;
+          const py = p.position.y - origin.y;
           const dirOf: Side | null =
             Math.abs(px) >= Math.abs(py) && px !== 0 ? (px > 0 ? "E" : "W") : py !== 0 ? (py > 0 ? "S" : "N") : null;
-          return dirOf === rolled && casterLos(state, caster, caster.position, p.position);
+          return dirOf === rolled && casterLos(state, caster, origin, p.position);
         });
         consumeCast(state, caster, inHand, mods, effect.keepInHand ?? false);
         state.turn.attackUsed = true;
@@ -5616,11 +5638,12 @@ function doCast(prev: GameState, cmd: Extract<Command, { type: "cast" }>): Comma
           kind: effect.physical ? "physical" : "spell",
           counters: [],
           waitingOn: along.id,
+          ...(cmd.via ? { origin } : {}),
         };
         missEvents.push({
           type: "spellCast", caster: caster.id, card: inHand, cardId: inHand.cardId,
           numberCards: mods.numbers, numberValue: mods.magnitude.numberValue,
-          from: caster.position, target: along.id, targetCell: along.position,
+          from: origin, target: along.id, targetCell: along.position,
         });
         return { ok: true, state, events: missEvents };
       }
@@ -5642,6 +5665,7 @@ function doCast(prev: GameState, cmd: Extract<Command, { type: "cast" }>): Comma
       counters: [],
       waitingOn: target.id,
       ...(mods.aroundCorner ? { bentCorner: true as const } : {}),
+      ...(cmd.via ? { origin } : {}),
     };
     state.lastSpellUsed[caster.id] = inHand.cardId;
     const events: GameEvent[] = [...wandEvents, ...preEvents];
@@ -5654,7 +5678,7 @@ function doCast(prev: GameState, cmd: Extract<Command, { type: "cast" }>): Comma
       numberCards: mods.numbers,
       numberValue: mods.magnitude.numberValue,
       amplifies: mods.amplifies.length,
-      from: caster.position,
+      from: origin,
       target: target.id,
       targetCell: target.position,
     });
@@ -5674,7 +5698,7 @@ function doCast(prev: GameState, cmd: Extract<Command, { type: "cast" }>): Comma
     cardId: inHand.cardId,
     numberCards: mods.numbers,
     numberValue: mods.magnitude.numberValue,
-    from: caster.position,
+    from: origin,
     target: cmd.target?.kind === "player" ? cmd.target.playerId : null,
     targetCell: cmd.target?.kind === "edge" || cmd.target?.kind === "cell" ? cmd.target.cell : null,
   });
@@ -6291,6 +6315,7 @@ function resolveStack(state: GameState, events: GameEvent[]): void {
         effect.onResolved({
           state, events,
           attacker: defender, defender: attacker,
+          origin: defender.position,
           damageDealt: 0, fullyStopped: false, reversed: false, duration: 0,
           stack: { ...stack, params: { ...stack.params, cardId: chosen } },
         });
@@ -6434,6 +6459,7 @@ function resolveStack(state: GameState, events: GameEvent[]): void {
       events,
       attacker,
       defender,
+      origin: stack.origin ?? attacker.position,
       damageDealt,
       fullyStopped: pipe.fullyStopped,
       reversed: pipe.reversed,
@@ -6472,11 +6498,12 @@ function goAwayRout(
   attacker: PlayerState,
   defender: PlayerState,
   squares: number,
+  origin: Cell = attacker.position,
 ): void {
   if (isLockedInPlace(state, defender.id)) return;
   const from = defender.position;
   const dist = (c: Cell) =>
-    Math.abs(attacker.position.x - c.x) + Math.abs(attacker.position.y - c.y);
+    Math.abs(origin.x - c.x) + Math.abs(origin.y - c.y);
   let heading: Side | null = null;
   let moved = 0;
   for (let i = 0; i < squares; i++) {
@@ -6527,9 +6554,10 @@ function knockBack(
   attacker: PlayerState,
   defender: PlayerState,
   squares: number,
+  origin: Cell = attacker.position,
 ): void {
-  const dx = defender.position.x - attacker.position.x;
+  const dx = defender.position.x - origin.x;
-  const dy = defender.position.y - attacker.position.y;
+  const dy = defender.position.y - origin.y;
   let dir: Side | null = null;
   if (Math.abs(dx) >= Math.abs(dy) && dx !== 0) dir = dx > 0 ? "E" : "W";
   else if (dy !== 0) dir = dy > 0 ? "S" : "N";

packages/engine/src/view.ts

@@ -220,20 +220,23 @@ export function fearCells(view: GameView): Set<string> {
  * reflects what this player knows (illusion walls they believe in block it).
  * The basis for the client's "dim the ineligible squares" targeting aid.
  */
-export function sightedCellsFor(view: GameView): Set<string> {
+export function sightedCellsFor(view: GameView, from?: Cell): Set<string> {
   const out = new Set<string>();
   const me = view.players.find((p) => p.id === view.you);
   if (!me) return out;
+  // Sight is taken from the viewer's square unless a cast leaves from
+  // elsewhere — an ALTER EGO's — in which case it is the double's.
+  const eye = from ?? me.position;
   const { board, blockers } = sightBasis(view);
   // In a dust cloud a wizard sees only their own square (rev 19).
-  if (dustAtEnd(view, me.position, me.position, true)) {
+  if (dustAtEnd(view, eye, eye, true)) {
-    out.add(`${me.position.x},${me.position.y}`);
+    out.add(`${eye.x},${eye.y}`);
     return out;
   }
   for (const key of Object.keys(board.cells)) {
     const [x, y] = key.split(",").map(Number) as [number, number];
-    if (dustAtEnd(view, me.position, { x, y })) continue;
+    if (dustAtEnd(view, eye, { x, y })) continue;
-    if (sightBetween(board, me.position, { x, y }, blockers)) out.add(key);
+    if (sightBetween(board, eye, { x, y }, blockers)) out.add(key);
   }
   // VISIONSTONE lets its bearer see through exactly one wall or door —
   // any one — so a square is also sighted if removing a single edge
@@ -248,7 +251,7 @@ export function sightedCellsFor(view: GameView): Set<string> {
       const opened = { ...board, edges };
       for (let i = unseen.length - 1; i >= 0; i--) {
         const [x, y] = unseen[i]!.split(",").map(Number) as [number, number];
-        if (sightBetween(opened, me.position, { x, y }, blockers)) {
+        if (sightBetween(opened, eye, { x, y }, blockers)) {
           out.add(unseen[i]!);
           unseen.splice(i, 1);
         }
@@ -263,8 +266,8 @@ export function sightedCellsFor(view: GameView): Set<string> {
  * plus every square visible from one of those — the caster looks to a middle
  * cell and the spell turns there, mirroring the engine's bentLos.
  */
-export function bentSightedCellsFor(view: GameView): Set<string> {
+export function bentSightedCellsFor(view: GameView, from?: Cell): Set<string> {
-  const out = sightedCellsFor(view);
+  const out = sightedCellsFor(view, from);
   const me = view.players.find((p) => p.id === view.you);
   if (!me) return out;
   const mids = [...out].map((k) => {
@@ -431,12 +434,12 @@ const SUMMON_CARD_IDS = new Set([
  * aid — mirroring the engine's own validation from the viewer's knowledge.
  * Null = this card's eligibility is not modeled; light everything.
  */
-export function eligibleCellsFor(view: GameView, cardId: string, bentCorner = false): Set<string> | null {
+export function eligibleCellsFor(view: GameView, cardId: string, bentCorner = false, from?: Cell): Set<string> | null {
   const me = view.players.find((p) => p.id === view.you);
   if (!me) return null;
   const cells = Object.keys(view.board.cells);
   const key = (x: number, y: number) => `${x},${y}`;
-  const sighted = bentCorner ? bentSightedCellsFor(view) : sightedCellsFor(view);
+  const sighted = bentCorner ? bentSightedCellsFor(view, from) : sightedCellsFor(view, from);
 
   if (CREATION_CARD_IDS.has(cardId)) {
     // emptySquareTarget: on the board, unoccupied by content, home, wizard,

packages/engine/test/creatures.test.ts

@@ -1,9 +1,10 @@
 import { describe, expect, it } from "vitest";
 import {
-  type CreatureState, applyCommand, activePlayer, boardView, creatureAt, type GameState, type PlayerId, createGame } from "../src/game";
+  type CreatureState, applyCommand, activePlayer, boardView, creatureAt, type GameState, type PlayerId, createGame, gameLos,
+} from "../src/game";
 import { cellKey, edgeKey, neighbor, opposite, SIDES, stepTarget, type Cell, type Side } from "../src/board";
 import type { CardInstance } from "../src/cards";
-import { newExpansionGame as newGame, must, drain, giveCard, toRound2, emptyNeighborCell, pushSustained } from "./helpers";
+import { newExpansionGame as newGame, must, drain, giveCard, toRound2, emptyNeighborCell, pushSustained, faceOff } from "./helpers";
 
 /** Summon a creature next to its creator (round 2+, consumes the attack). */
 function summon(state: GameState, playerId: PlayerId, kind: string, tag = "S") {
@@ -961,3 +962,38 @@ describe("the imp's fire is a spell (rev 8)", () => {
     expect(after.alive).toBe(true);
   });
 });
+
+describe("the alter ego casts from its own square", () => {
+  it("a fireball leaves from the double, by the double's sight, and answers to the caster", () => {
+    let { state } = newGame(42);
+    state = toRound2(state);
+    const { attacker, defender } = faceOff(state);
+    const a = state.players.find((p) => p.id === attacker)!;
+    const d = state.players.find((p) => p.id === defender)!;
+    const ego = giveCard(state, attacker, "alter-ego");
+    state = must(state, attacker, { type: "cast", instanceId: ego.instanceId });
+    const double = state.creatures.find((c) => c.kind === "alter-ego" && c.controllerId === attacker)!;
+    expect(cellKey(double.position)).toBe(cellKey(a.position));
+    // The caster steps out of the defender's sight; the double keeps it.
+    const view = boardView(state);
+    const hidden = Object.keys(view.cells).map((k) => { const [x, y] = k.split(",").map(Number) as [number, number]; return { x, y }; })
+      .find((c) => !gameLos(state, c, d.position) && !state.squareContents[cellKey(c)] && !view.homes.some((h) => cellKey(h) === cellKey(c)));
+    expect(hidden).toBeDefined();
+    const me = state.players.find((p) => p.id === attacker)!;
+    me.position = { ...hidden! };
+    const fb = giveCard(state, attacker, "fireball");
+    const blind = applyCommand(state, attacker, { type: "cast", instanceId: fb.instanceId, target: { kind: "player", playerId: defender } });
+    expect(blind.ok).toBe(false);
+    const wrong = applyCommand(state, attacker, { type: "cast", instanceId: fb.instanceId, target: { kind: "player", playerId: defender }, via: "no-such-double" });
+    expect(wrong.ok).toBe(false);
+    const viaEgo = applyCommand(state, attacker, { type: "cast", instanceId: fb.instanceId, target: { kind: "player", playerId: defender }, via: double.id });
+    expect(viaEgo.ok).toBe(true);
+    if (!viaEgo.ok) return;
+    expect(viaEgo.state.stack?.attackerId).toBe(attacker);
+    expect(cellKey(viaEgo.state.stack!.origin!)).toBe(cellKey(double.position));
+    const cast = viaEgo.events.find((e) => e.type === "spellCast");
+    expect(cast && cast.type === "spellCast" ? cellKey(cast.from) : null).toBe(cellKey(double.position));
+    const done = must(viaEgo.state, defender, { type: "pass" });
+    expect(done.players.find((p) => p.id === defender)!.life).toBe(10);
+  });
+});

packages/web/src/App.svelte

@@ -590,8 +590,15 @@
 
   /** Attachment plumbing for a cast command: the chosen mods and the
    * attached NUMBER ride along (an explicit numberInstanceIds wins). */
+  /** Your ALTER EGO, when it is the selected token: casts leave from its square. */
+  const castingDouble = $derived(
+    selectedCreature && view
+      ? view.creatures.find((c) => c.id === selectedCreature && c.kind === "alter-ego" && c.controllerId === view!.you) ?? null
+      : null,
+  );
   function withMods<T extends Parameters<typeof net.command>[0] & { type: "cast" }>(cmd: T): T {
     applyMods(cmd);
+    if (castingDouble && cmd.target) cmd.via = castingDouble.id;
     if (attachedNumber && !cmd.numberInstanceIds) {
       cmd.numberInstanceIds = [attachedNumber.instanceId];
     }
@@ -1150,7 +1157,7 @@
 
   function clickPlayer(playerId: string) {
     if (!view || !yourMoment) return;
-    if (selectedCreature) {
+    if (selectedCreature && !(castingDouble && selectedCard)) {
       dispatch({ type: "creatureAttack", creatureId: selectedCreature, targetId: playerId });
       selectedCreature = null;
       return;
@@ -1540,12 +1547,9 @@
       .filter((t) => t.kind !== "blocked")
       .map((t) => cellKey(t.to));
   });
-  /** The first stride of a first game gets one line on the board itself. */
+  /** The first stride of a first game gets one line above the board —
-  const stepCaption = $derived(
+   * off the maze, so the walls around the wizard stay in plain sight. */
-    stepLight && view && me && view.turn.round === 1 && view.turn.movementUsed === 0
+  const stepCaption = $derived(stepLight && view && me && view.turn.round === 1 && view.turn.movementUsed === 0);
-      ? { cell: me.position, text: "This is you — tap a lit square to walk" }
-      : null,
-  );
   const litCells = $derived.by(() => {
     if (view && me && !selectedDef && stepLight) return new Set([cellKey(me.position), ...stepCells]);
     if (!view || !selectedDef || !yourMoment) return null;
@@ -1553,10 +1557,10 @@
     if (!me) return null;
     const bent = attachedMods.some((m) => m.cardId === "around-the-corner");
     if (CELL_CARDS.has(selectedCard!.cardId)) {
-      return eligibleCellsFor(view, selectedCard!.cardId, bent);
+      return eligibleCellsFor(view, selectedCard!.cardId, bent, castingDouble?.position);
     }
     if (selectedDef.adjacent === true) {
-      const { x, y } = me.position;
+      const { x, y } = castingDouble?.position ?? me.position;
       return new Set(
         [[x, y], [x + 1, y], [x - 1, y], [x, y + 1], [x, y - 1]]
           .map(([cx, cy]) => `${cx},${cy}`)
@@ -1564,7 +1568,7 @@
       );
     }
     if (selectedDef.los !== true) return null;
-    return bent ? bentSightedCellsFor(view) : sightedCellsFor(view);
+    return bent ? bentSightedCellsFor(view, castingDouble?.position) : sightedCellsFor(view, castingDouble?.position);
   });
 
   /** Creatures awaiting your orders this turn (yours + any democratic monster). */
@@ -2479,8 +2483,12 @@
             {#if selectedCreature && !selectedDef}
               {@const sc = view.creatures.find((c) => c.id === selectedCreature)}
               {#if sc}
-                <span>Commanding <strong>{cardDef(sc.kind).name}</strong> — {creatureStats(sc)}.
+                {#if sc.kind === "alter-ego"}
-                  Tap a square beside it to march, a target in its square to attack.</span>
+                  <span>Your <strong>double</strong> stands ready — select a card and it casts from the double's square, by the double's sight.</span>
+                {:else}
+                  <span>Commanding <strong>{cardDef(sc.kind).name}</strong> — {creatureStats(sc)}.
+                    Tap a square beside it to march, a target in its square to attack.</span>
+                {/if}
                 {#if dmWarnCell}
                   <span class="hint-alert">⚠ it will claw YOU the moment it enters your square — tap again if you mean it</span>
                 {/if}
@@ -2673,6 +2681,12 @@
             </button>
           </div>
         {/if}
+        {#if stepCaption && me}
+          <div class="step-caption">
+            <span class="step-chip" style:background={playerColor(me.id)}></span>
+            This is you — tap a lit square beside your wizard to walk
+          </div>
+        {/if}
         <div class="table-stack" class:fpv-primary={prefs.liveFp && !!view.you && !net.spectating}>
         {#if prefs.liveFp && view.you && !net.spectating}
           <LiveFirstPerson {view} batch={fpBatch} onhide={() => setPref("liveFp", false)}
@@ -2712,7 +2726,6 @@
           onEdgePeek={(tip) => (peekEdge = tip)}
           {litCells}
           spotCells={stepCells}
-          spotCaption={stepCaption}
           {sightTrace}
           povFacing={prefs.liveFp && view.you && !net.spectating ? fpvFacing : null}
           povCreatureId={prefs.liveFp && !net.spectating ? fpvBody : null}
@@ -3487,8 +3500,31 @@
     margin: 0.2rem 0 0.1rem;
   }
   /* The eyes toggle floats over the board's corner so it costs the maze no height. */
-  .board-zone { position: relative; }
+  .board-zone { position: relative; flex-direction: column; align-items: stretch; }
   .view-toggle { position: absolute; top: 0.25rem; right: 0.25rem; z-index: 3; }
+  .step-caption {
+    align-self: flex-start;
+    max-width: calc(100% - 11rem);
+    margin: 0 0 0.4rem 0.4rem;
+    padding: 0.3rem 0.8rem;
+    border-radius: 999px;
+    background: rgba(28, 22, 12, 0.92);
+    border: 1.5px solid #f2cf5b;
+    color: #f7ecc8;
+    font-family: "Oswald", sans-serif;
+    font-size: 0.85rem;
+    letter-spacing: 0.02em;
+    display: flex;
+    align-items: center;
+    gap: 0.45rem;
+  }
+  .step-chip {
+    display: inline-block;
+    width: 0.8em;
+    height: 0.8em;
+    border-radius: 2px;
+    border: 1.5px solid #f7ecc8;
+  }
   .boxlid-tag {
     font-size: 0.95rem;
     color: #6b5a41;

packages/web/src/Board.svelte

@@ -35,7 +35,6 @@
     markedCells = null,
     litCells = null,
     spotCells = [],
-    spotCaption = null,
     markedSector = null,
     ghostSlots = null,
     onGhostClick,
@@ -70,8 +69,6 @@
     litCells?: Set<string> | null;
     /** The step light's squares: a pulsing rim on each. */
     spotCells?: string[];
-    /** One line hung above a square — the first stride's cue. */
-    spotCaption?: { cell: { x: number; y: number }; text: string } | null;
     /** Origin of a picked-up 5x5 sector: the whole sector outlines as taken. */
     markedSector?: { x: number; y: number } | null;
     /** Empty 5x5 slot origins a sector may land on — drawn as dashed ground
@@ -697,17 +694,6 @@
     {@const sy = Number(key.split(",")[1])}
     <rect x={sx * CELL + 3} y={sy * CELL + 3} width={CELL - 6} height={CELL - 6} class="spot-cell" rx="5" />
   {/each}
-  {#if spotCaption}
-    {@const cols = Math.max(...Object.keys(view.board.cells).map((k) => Number(k.split(",")[0]))) + 1}
-    {@const cw = spotCaption.text.length * 6.6 + 20}
-    {@const cx = Math.min(Math.max(spotCaption.cell.x * CELL + CELL / 2, cw / 2 + 4), cols * CELL - cw / 2 - 4)}
-    {@const above = spotCaption.cell.y > 0}
-    {@const cy = above ? spotCaption.cell.y * CELL - 14 : (spotCaption.cell.y + 1) * CELL + 14}
-    <g class="spot-caption" transform={`translate(${cx}, ${cy})`}>
-      <rect x={-cw / 2} y={-12} width={cw} height={24} rx="12" />
-      <text x="0" y="4">{spotCaption.text}</text>
-    </g>
-  {/if}
   <!-- FEAR's bubble: the three-space diamond, through walls, wrapping the rim -->
   {#each fearAura as key (key)}
     {@const bx = Number(key.split(",")[0])}
@@ -865,15 +851,6 @@
     0%, 100% { opacity: 0.35; }
     50% { opacity: 1; }
   }
-  .spot-caption { pointer-events: none; }
-  .spot-caption rect { fill: rgba(28, 22, 12, 0.92); stroke: #f2cf5b; stroke-width: 1.5; }
-  .spot-caption text {
-    fill: #f7ecc8;
-    font-size: 12px;
-    font-family: "Oswald", "Helvetica Neue", Arial, sans-serif;
-    letter-spacing: 0.02em;
-    text-anchor: middle;
-  }
   .marked-cell {
     fill: rgba(211, 133, 43, 0.18);
     stroke: #d3852b;