diff --git a/AGENTS.md b/AGENTS.md
index d56727a..13117e5 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -778,8 +778,17 @@ source CI can refresh. Four things to know about it:
   (`To Temper Thyself and Journey Far` vs `… Cycle 5`, and `Stygian Onslaught` vs
   `…: Battle of the Starburst`). In `merge.ts`, higher priority breaks ties when confidence is equal
   (0.85). If Fandom won those near-matches, the event IDs would change and readers' localStorage
-  completion marks would silently orphan. With Game8 prioritized: 0 IDs lost, 11 net-new events added,
-  0 conflicts, and 5 corroborated events earning confidence bonuses.
+  completion marks would silently orphan. With Game8 prioritized: 0 IDs lost, 10 net-new events added,
+  0 conflicts, and 6 corroborated events earning confidence bonuses. (This read 11 and 5 until
+  2026-10-14: the eleventh "new" event was the battle pass, listed twice — next bullet.)
+- **Game8 labels a battle pass; Fandom does not, and that put every pass on the calendar twice.**
+  Game8 heads it `Battle Pass - Moontrace`, Fandom lists `Moontrace` and files the category under
+  `Type(s)`, so the two minted different IDs and no merge rule could pair them — overlap scores 0.5,
+  and a one-word base is under `titleExtends`' floor. Reported by a reader on 2026-10-14; the pinned
+  fixtures show it from the day this source landed. `eventName` (`parsers/game8.ts`) now drops the
+  label so both sources mint one ID, and `src/client/state/retiredIds.ts` moves readers' marks off
+  the two IDs that changed. The general lesson: **a second source needs its whole overlap with the
+  first read row by row, not counted** — a duplicate looks exactly like a net-new event in a tally.
 - **The 336-day event raised the duration ceiling to 365 days.** Genshin's anniversary 5-star selection
   runs 336 days (`2025-10-22` → `2026-09-23`), correctly dated on this wiki. This motivated raising the
   sanity ceiling in `test/adapters/game8.test.ts` and `docs/INGESTION.md` from 180 to 365 days.
diff --git a/docs/DATA-MODEL.md b/docs/DATA-MODEL.md
index ad4997f..bf35bdd 100644
--- a/docs/DATA-MODEL.md
+++ b/docs/DATA-MODEL.md
@@ -116,7 +116,9 @@ server-side (the server never had the data). If the scheme must change, ship a c
 migration that reads the old keys and remaps them, and keep that migration for at least a year.
 
 **A parser fix can move IDs too, and gets the same treatment.** `src/client/state/retiredIds.ts`
-holds an explicit table of IDs the feed stopped publishing and what each became. On every load and
+holds an explicit table of IDs the feed stopped publishing and what each became — first used on
+2026-10-14, when Game8's Genshin parser stopped keeping `Battle Pass -` in front of a pass's name
+(the label had put every pass on the calendar twice beside Fandom's bare name). On every load and
 every import, `progress`, `daily` and `ignored` entries under a retired ID **move** to the new one:
 
 - **A move inside the same storage key, not a copy, and not a deleted key.** The mark survives under
@@ -127,7 +129,7 @@ every import, `progress`, `daily` and `ignored` entries under a retired ID **mov
   held, because both rows were the reader's own.
 - **An unreadable entry is left where it is.** These run in `useState` initialisers, where a throw is
   a blank screen.
-- **A table, never a pattern**, and each entry kept for at least a year.
+- **A table, never a pattern**, and kept until at least 2027-10-14.
 
 The date suffix disambiguates reruns of the same event. Title is slugified from the *source's*
 title, so a wiki renaming an event creates a new ID — reconciliation detects this as a near-match
diff --git a/docs/SOURCES.md b/docs/SOURCES.md
index 1010bcb..f841d08 100644
--- a/docs/SOURCES.md
+++ b/docs/SOURCES.md
@@ -809,7 +809,7 @@ note is what stops the next person re-deriving the reason it does not.
 - **Title extraction:** Display text of the caption link beneath the banner image is taken. Link `title` (parent subpage) and `img alt` (uploaded image file name) are rejected to prevent corrupting event titles and IDs.
 - **Run-date suffixes:** Recurring event run dates (`2026-09-14`) in subpage names are stripped so dates aren't duplicated.
 - **Currency:** `latestBoundaryMs` is checked for day-precision boundaries so events aren't retired before all server regions roll.
-- **Priority & IDs:** Game8 is assigned `priority: 10` while Fandom is default/0. Two live events differ slightly in naming (`To Temper Thyself and Journey Far` vs `… Cycle 5`, and `Stygian Onslaught` vs `…: Battle of the Starburst`). Game8's higher priority breaks near-match ties in `merge.ts`, ensuring existing localStorage event IDs survive and reader completion marks remain intact. Fandom contributes 11 net-new events Game8 missed, 0 date conflicts occur, and overlapping events gain corroboration bonuses.
+- **Priority & IDs:** Game8 is assigned `priority: 10` while Fandom is default/0. Two live events differ slightly in naming (`To Temper Thyself and Journey Far` vs `… Cycle 5`, and `Stygian Onslaught` vs `…: Battle of the Starburst`). Game8's higher priority breaks near-match ties in `merge.ts`, ensuring existing localStorage event IDs survive and reader completion marks remain intact. Fandom contributes 10 net-new events Game8 missed, 0 date conflicts occur, and overlapping events gain corroboration bonuses. (Recorded as 11 until 2026-10-14: one was Game8's `Battle Pass - Frostfarer` beside Fandom's `Frostfarer`, the same event under two IDs. Game8's parser now drops that label; AGENTS.md § Fandom has the rest, including the anniversary selectors, still listed twice.)
 - **336-day event:** Genshin's anniversary 5-star selection runs 336 days (`2025-10-22` → `2026-09-23`), prompting the test duration ceiling to be raised from 180 to 365 days across the test suite and ingestion specs.
 
 ## 16. hololive Dreams — the wiki lapsed (2026-10-14); nothing else can be fetched
diff --git a/fixtures/genshin/game8-events-2026-08-14.expected.json b/fixtures/genshin/game8-events-2026-08-14.expected.json
index f5421c5..56ff6b4 100644
--- a/fixtures/genshin/game8-events-2026-08-14.expected.json
+++ b/fixtures/genshin/game8-events-2026-08-14.expected.json
@@ -21,14 +21,14 @@
     "updatedAt": "2026-08-14T00:00:00.000Z"
   },
   {
-    "id": "genshin:battle-pass-frostfarer:2026-08-12",
+    "id": "genshin:character-test-runs:2026-08-12",
     "game": "genshin",
-    "title": "Battle Pass - Frostfarer",
-    "type": "other",
-    "summary": "Participate in the free Sojourner's Battle Pass and the for-purchase Gnostic Hymn to receive prizes as you increase your BP Level.",
+    "title": "Character Test Runs",
+    "type": "challenge",
+    "summary": "The Character Test Run is available at the same time as the Character Banners in Phase 1 of Version 7.0 from August 12, 2026 to September 1, 2026!",
     "startsAt": "2026-08-12T00:00:00.000Z",
     "startPrecision": "day",
-    "endsAt": "2026-09-21T00:00:00.000Z",
+    "endsAt": "2026-09-01T00:00:00.000Z",
     "endPrecision": "day",
     "regionScoped": false,
     "regionEnds": null,
@@ -42,14 +42,14 @@
     "updatedAt": "2026-08-14T00:00:00.000Z"
   },
   {
-    "id": "genshin:character-test-runs:2026-08-12",
+    "id": "genshin:frostfarer:2026-08-12",
     "game": "genshin",
-    "title": "Character Test Runs",
-    "type": "challenge",
-    "summary": "The Character Test Run is available at the same time as the Character Banners in Phase 1 of Version 7.0 from August 12, 2026 to September 1, 2026!",
+    "title": "Frostfarer",
+    "type": "other",
+    "summary": "Participate in the free Sojourner's Battle Pass and the for-purchase Gnostic Hymn to receive prizes as you increase your BP Level.",
     "startsAt": "2026-08-12T00:00:00.000Z",
     "startPrecision": "day",
-    "endsAt": "2026-09-01T00:00:00.000Z",
+    "endsAt": "2026-09-21T00:00:00.000Z",
     "endPrecision": "day",
     "regionScoped": false,
     "regionEnds": null,
diff --git a/src/client/state/retiredIds.ts b/src/client/state/retiredIds.ts
index 0311856..45b7969 100644
--- a/src/client/state/retiredIds.ts
+++ b/src/client/state/retiredIds.ts
@@ -10,14 +10,21 @@ export type CarryTable = Readonly<Record<string, string>>;
  *
  * An event id is a localStorage key (AGENTS.md § Event IDs are localStorage
  * keys), so an id that moves takes the reader's marks with it unless they are
- * carried across. A change that moves ids — a parser fix that renames a title
- * is the usual one — lands its entries here, in the same commit.
+ * carried across. These moved on 2026-10-14, when the Game8 parser stopped
+ * keeping `Battle Pass -` in front of Genshin's pass names: Fandom had always
+ * published the bare name, and the two ids put every pass on the calendar
+ * twice (docs/superpowers/specs/2026-10-14-genshin-duplicates-design.md).
  *
- * An explicit table, never a pattern: a pattern would also catch an id nobody
- * retired. Keep each entry for at least a year — a reader who has not opened
- * the app since still has marks under the old id.
+ * An explicit table, never a pattern: the battle passes are the only two such
+ * ids that ever shipped (git history of snapshots/ and fixtures/), and a
+ * pattern would also catch an id nobody retired. Keep it until at least
+ * 2027-10-14 — a reader who has not opened the app since still has marks under
+ * the old ids.
  */
-export const RETIRED_IDS: CarryTable = {};
+export const RETIRED_IDS: CarryTable = {
+  "genshin:battle-pass-frostfarer:2026-08-12": "genshin:frostfarer:2026-08-12",
+  "genshin:battle-pass-moontrace:2026-09-23": "genshin:moontrace:2026-09-23",
+};
 
 /**
  * Move each entry under an old id in `table` to its replacement.
diff --git a/src/ingest/parsers/game8.ts b/src/ingest/parsers/game8.ts
index 15f7eb9..f77615f 100644
--- a/src/ingest/parsers/game8.ts
+++ b/src/ingest/parsers/game8.ts
@@ -452,6 +452,19 @@ export function inferType(title: string): EventType {
   return "other";
 }
 
+/**
+ * The event's name without a category label in front of it.
+ *
+ * Genshin's page heads its pass `Battle Pass - Moontrace`; the Fandom wiki
+ * lists the same event as `Moontrace` and files the category in a column. The
+ * label is not the name, and keeping it minted a second ID for one event, so
+ * the calendar showed every battle pass twice. Stripping it moved this
+ * source's battle-pass IDs, which is why `retiredIds.ts` exists.
+ */
+export function eventName(title: string): string {
+  return title.replace(/^battle pass\s*[-–—:]\s*(?=\S)/i, "");
+}
+
 function toEvent(c: Candidate, ctx: ParseContext): GachaEvent {
   // Confidence reflects how much the source actually pinned down. Day precision
   // and unknown ends are legitimate and common, but they are weaker evidence
@@ -461,11 +474,12 @@ function toEvent(c: Candidate, ctx: ParseContext): GachaEvent {
   if (c.end === null) confidence -= 0.15;
   else if (c.end.precision === "day") confidence -= 0.05;
 
+  const title = eventName(c.title);
   return {
-    id: eventId(ctx.game, c.title, c.start.iso),
+    id: eventId(ctx.game, title, c.start.iso),
     game: ctx.game,
-    title: c.title,
-    type: inferType(c.title),
+    title,
+    type: inferType(title),
     summary: c.summary,
     startsAt: c.start.iso,
     startPrecision: c.start.precision,
diff --git a/test/adapters/game8.test.ts b/test/adapters/game8.test.ts
index 1998bf8..5fe0add 100644
--- a/test/adapters/game8.test.ts
+++ b/test/adapters/game8.test.ts
@@ -164,11 +164,23 @@ describe("genshin fixture specifics", () => {
 
     // Sourced from a one-cell "Availability Period" range rather than
     // Start/End rows — the other table shape on the same page.
-    expect(byTitle.get("Battle Pass - Frostfarer")?.endsAt).toBe(
+    expect(byTitle.get("Frostfarer")?.endsAt).toBe(
       "2026-09-21T00:00:00.000Z",
     );
   });
 
+  test("a leading Battle Pass label is not part of the name", async () => {
+    // Fandom lists the same pass as plain `Frostfarer` and puts the category in
+    // its Type(s) column. Keeping Game8's label minted a second ID for one
+    // event, and the calendar showed every battle pass twice.
+    const events = await runAdapter(
+      genshinGame8,
+      "fixtures/genshin/game8-events-2026-08-14",
+    );
+    expect(events.some((e) => /^battle pass/i.test(e.title))).toBe(false);
+    expect(events.map((e) => e.id)).toContain("genshin:frostfarer:2026-08-12");
+  });
+
   test("year-less summary rows produce no events", async () => {
     // The page's summary tables show "08/12 - 08/24" with no year. Those must
     // be skipped, not year-guessed — and they must not duplicate the detail
@@ -1967,12 +1979,15 @@ describe("Genshin Impact wiki (the fifth Fandom template)", () => {
       expect(result.events.map((e) => e.id)).toContain(expected.id);
     }
 
-    // Fandom contributes net-new events Game8 did not list (total 20 merged events)
-    expect(result.events.length).toBe(20);
+    // Fandom contributes net-new events Game8 did not list (total 19 merged
+    // events). This read 20 until 2026-10-14, and the twentieth was the battle
+    // pass listed twice — `Battle Pass - Frostfarer` beside `Frostfarer`.
+    expect(result.events.length).toBe(19);
+    expect(result.events.filter((e) => /frostfarer/i.test(e.title))).toHaveLength(1);
     expect(result.conflicts).toHaveLength(0);
 
     // Corroboration bonus applies to overlapping events (0.85 -> 0.95)
     const corroborated = result.events.filter((e) => e.confidence > 0.85);
-    expect(corroborated.length).toBe(5);
+    expect(corroborated.length).toBe(6);
   });
 });
diff --git a/test/retired-ids.test.ts b/test/retired-ids.test.ts
index bdaed84..376759b 100644
--- a/test/retired-ids.test.ts
+++ b/test/retired-ids.test.ts
@@ -1,5 +1,7 @@
 import { describe, expect, test } from "bun:test";
+import { parseImportData } from "../src/client/state/export.ts";
 import {
+  RETIRED_IDS,
   carryForward,
   carryDaily,
   carryMarks,
@@ -94,3 +96,48 @@ describe("when the reader marked both rows", () => {
     expect(out).toEqual({ [NEW]: { at: "2026-09-24T00:00:00.000Z" } });
   });
 });
+
+const PASS = "genshin:battle-pass-moontrace:2026-09-23";
+const BARE = "genshin:moontrace:2026-09-23";
+
+describe("RETIRED_IDS", () => {
+  test("names the two battle passes Game8 minted with their label", () => {
+    expect(RETIRED_IDS[PASS]).toBe(BARE);
+    expect(RETIRED_IDS["genshin:battle-pass-frostfarer:2026-08-12"]).toBe(
+      "genshin:frostfarer:2026-08-12",
+    );
+  });
+
+  test("never retires an id onto another retired id", () => {
+    for (const to of Object.values(RETIRED_IDS)) {
+      expect(RETIRED_IDS[to]).toBeUndefined();
+    }
+  });
+
+  test("is the table a load uses when none is given", () => {
+    const out = carryMarks({ [PASS]: { at: "2026-09-24T00:00:00.000Z" } });
+    expect(Object.keys(out)).toEqual([BARE]);
+  });
+});
+
+describe("an export made before the ids moved", () => {
+  test("imports onto the new ids", () => {
+    const data = parseImportData({
+      format: "gacha-tracker-export",
+      progress: { [PASS]: { status: "done", at: "2026-10-01T00:00:00.000Z" } },
+      daily: { [PASS]: { days: ["2026-09-24"], at: "2026-09-24T00:00:00.000Z" } },
+      ignored: { [PASS]: { at: "2026-09-24T00:00:00.000Z" } },
+    });
+    expect(Object.keys(data?.progress ?? {})).toEqual([BARE]);
+    expect(Object.keys(data?.daily ?? {})).toEqual([BARE]);
+    expect(Object.keys(data?.ignored ?? {})).toEqual([BARE]);
+  });
+
+  test("so does one from before progress existed", () => {
+    const data = parseImportData({
+      format: "gacha-tracker-export",
+      completions: { [PASS]: { at: "2026-10-01T00:00:00.000Z" } },
+    });
+    expect(data?.progress?.[BARE]?.status).toBe("done");
+  });
+});