diff --git a/web/scripts/seat-shuffle.test.mjs b/web/scripts/seat-shuffle.test.mjs
new file mode 100644
index 0000000..2734591
--- /dev/null
+++ b/web/scripts/seat-shuffle.test.mjs
@@ -0,0 +1,86 @@
+/**
+ * The reroll control on a bot seat, on the challenge screen.
+ *
+ * A bot seat's camo is rolled once and cached in `rolled`, keyed by
+ * scenario-path and slot name, so the AI fights in exactly the pattern the
+ * preview showed. The reroll button's whole job is to clear that one cache
+ * entry, roll again, and tell the preview to redraw — get any of the three
+ * wrong and either nothing happens on click, or the preview and the launch
+ * end up disagreeing about the AI's camo again.
+ *
+ * Structural, like this screen's other checks. There is no DOM under `npm
+ * test`, and a wrong wiring here does not throw — the button still renders
+ * and still looks clickable, it just does not do the one thing it exists for.
+ *
+ * Run with `npm test`.
+ */
+import { test } from "node:test";
+import assert from "node:assert/strict";
+import { readFile } from "node:fs/promises";
+import { join } from "node:path";
+import { fileURLToPath } from "node:url";
+
+const web = fileURLToPath(new URL("../", import.meta.url));
+const source = await readFile(join(web, "src/screens/challenge.ts"), "utf8");
+
+function shuffleBlock() {
+  const block = source.match(
+    /const shuffle = el\("button", \{[\s\S]*?\}\);\s*const setShuffle[\s\S]*?shuffle\.addEventListener\("click", \(\) => \{([\s\S]*?)\}\);/,
+  );
+  assert.ok(block, "the reroll button's click handler moved or was renamed");
+  return block[1];
+}
+
+test("reroll clears the cached roll before asking for a new one", () => {
+  const body = shuffleBlock();
+  const deleteAt = body.indexOf("rolled.delete(");
+  const rerollAt = body.indexOf("rolledFor(slot.name)");
+  assert.ok(deleteAt !== -1, "the click handler no longer clears the cache");
+  assert.ok(rerollAt !== -1, "the click handler no longer rolls again");
+  assert.ok(
+    deleteAt < rerollAt,
+    "rolledFor(slot.name) would just hand back the old roll unless the " +
+      "cache is cleared first",
+  );
+});
+
+test("reroll clears the same key rolledFor reads", () => {
+  const keyed = source.match(
+    /function rolledFor\(slot: string\): Promise<Rolled \| null> \{\s*const key = `([^`]*)`;/,
+  );
+  assert.ok(keyed, "rolledFor's cache key moved or was renamed");
+  const body = shuffleBlock();
+  assert.match(
+    body,
+    /rolled\.delete\(`\$\{scenario\?\.path\}\|\$\{slot\.name\}`\)/,
+    `the click handler clears a different key than rolledFor reads ` +
+      `(rolledFor uses \`${keyed[1]}\`); a mismatch here leaves the old ` +
+      "roll in place",
+  );
+});
+
+test("reroll tells the preview to redraw", () => {
+  const body = shuffleBlock();
+  assert.match(
+    body,
+    /refreshPreview\(\)/,
+    "the click handler no longer calls refreshPreview, so the preview " +
+      "would keep showing the old camo after a reroll",
+  );
+});
+
+test("the reroll button only shows on a bot seat", () => {
+  assert.match(
+    source,
+    /const setShuffle = \(choice: string\): void => \{\s*shuffle\.hidden = choice !== "bot";\s*\};/,
+    "the reroll button is no longer hidden for self/player seats — it has " +
+      "nothing to reroll for either",
+  );
+  assert.match(
+    source,
+    /select\.addEventListener\("change", \(\) => \{[\s\S]*?setShuffle\(select\.value\);[\s\S]*?\}\);/,
+    "the seat select's change handler no longer updates the reroll " +
+      "button's visibility, so it would keep showing after switching a " +
+      "seat away from the AI",
+  );
+});
diff --git a/web/src/screens/challenge.ts b/web/src/screens/challenge.ts
index 0b59b19..8737314 100644
--- a/web/src/screens/challenge.ts
+++ b/web/src/screens/challenge.ts
@@ -700,6 +700,25 @@ export function challengeScreen(session: Session, mode: ChallengeMode): Node[] {
         }
       };
       setFace(seats.get(slot.name) ?? "bot");
+      // A fresh roll for this seat's bot camo, only meaningful while it is
+      // actually a bot seat — a self or player seat has nothing here to
+      // reroll. Hidden rather than absent, so the row does not reflow when
+      // the select flips it on.
+      const shuffle = el("button", {
+        type: "button",
+        className: "secondary small-btn seat-shuffle",
+        textContent: "⟳",
+        "aria-label": `Reroll ${slot.name}'s camo`,
+      });
+      const setShuffle = (choice: string): void => {
+        shuffle.hidden = choice !== "bot";
+      };
+      setShuffle(seats.get(slot.name) ?? "bot");
+      shuffle.addEventListener("click", () => {
+        rolled.delete(`${scenario?.path}|${slot.name}`);
+        void rolledFor(slot.name);
+        refreshPreview();
+      });
       const options: [SeatChoice, string][] = [
         ["self", `You${session.handle ? ` (${at(session.handle)})` : ""}`],
         ["bot", "Play against AI"],
@@ -721,6 +740,7 @@ export function challengeScreen(session: Session, mode: ChallengeMode): Node[] {
       select.addEventListener("change", () => {
         seats.set(slot.name, select.value as SeatChoice);
         setFace(select.value);
+        setShuffle(select.value);
         updateNext();
         // The seat's camo and caption both follow who holds it.
         refreshPreview();
@@ -734,7 +754,7 @@ export function challengeScreen(session: Session, mode: ChallengeMode): Node[] {
               textContent: slot.units.join(", "),
             }),
           ]),
-          el("div", { className: "seat-pick" }, [face, select]),
+          el("div", { className: "seat-pick" }, [face, select, shuffle]),
         ]),
       );
     }
diff --git a/web/src/styles.css b/web/src/styles.css
index e6b436a..6cbd556 100644
--- a/web/src/styles.css
+++ b/web/src/styles.css
@@ -1597,6 +1597,13 @@ footer .debug {
   object-fit: cover;
 }
 
+/* Rerolls a bot seat's camo. Chrome from .small-btn; only the glyph is its
+   own, and line-height keeps a lone character centred in the padding. */
+.seat-shuffle {
+  padding: 0.35rem 0.5rem;
+  line-height: 1;
+}
+
 .lineup-chip:not([disabled]):hover {
   border-color: var(--accent);
 }