IDEAS.md

@@ -8,7 +8,7 @@ A running list of planned features and content additions. Strike through items a
 
 - [x] **Offline earnings** — When returning to the game, earn a percentage of what you'd have earned offline (cap at ~8–12 hours). Upgradeable via the prestige shop to increase the % and the time cap. Essential for an idle game!
 
-- [ ] **Second prestige layer (Transcendence)** — Unlocked after ~10 prestiges. Sacrifice all runestones for a new currency ("Echoes"?). Echoes are permanent account-wide currency that persist across prestiges. Has its own upgrade tree with truly game-changing bonuses. Gives endgame players a long-term goal.
+- [x] **Second prestige layer (Transcendence)** — Unlocked after ~10 prestiges. Sacrifice all runestones for a new currency ("Echoes"?). Echoes are permanent account-wide currency that persist across prestiges. Has its own upgrade tree with truly game-changing bonuses. Gives endgame players a long-term goal.
 
 - [x] **Daily challenges** — Three rotating objectives each day (e.g. kill X boss, earn X gold this run, complete X quests). Reward bonus crystals. Encourages daily logins even when idling comfortably.
 
@@ -46,4 +46,4 @@ A running list of planned features and content additions. Strike through items a
 6. ~~Equipment set bonuses~~ ✅
 7. ~~Auto-prestige toggle~~ ✅
 8. ~~The Codex / Lore Book~~ ✅
-9. Second prestige layer / Transcendence (big feature, save for later)
+9. ✅ Second prestige layer / Transcendence (big feature, save for later)

apps/api/src/data/transcendenceUpgrades.ts

@@ -0,0 +1,133 @@
+import type { TranscendenceUpgrade } from "@elysium/types";
+
+export const DEFAULT_TRANSCENDENCE_UPGRADES: TranscendenceUpgrade[] = [
+  // ── Income multipliers ──────────────────────────────────────────────────────
+  {
+    id: "echo_income_1",
+    name: "Whisper of Power",
+    description: "The echoes of past runs linger, amplifying your guild's income by 25%.",
+    category: "income",
+    cost: 5,
+    multiplier: 1.25,
+  },
+  {
+    id: "echo_income_2",
+    name: "Resonance",
+    description: "Your transcendent experience resonates through your guild, boosting income by 50%.",
+    category: "income",
+    cost: 10,
+    multiplier: 1.5,
+  },
+  {
+    id: "echo_income_3",
+    name: "Harmonic Surge",
+    description: "The harmony of multiple timelines surges through your guild, doubling its income.",
+    category: "income",
+    cost: 20,
+    multiplier: 2.0,
+  },
+  {
+    id: "echo_income_4",
+    name: "Ethereal Overflow",
+    description: "Ethereal energy overflows from your transcendence, tripling your guild's income.",
+    category: "income",
+    cost: 40,
+    multiplier: 3.0,
+  },
+  {
+    id: "echo_income_5",
+    name: "Infinite Chorus",
+    description: "The infinite chorus of every run you've ever played amplifies your guild fivefold.",
+    category: "income",
+    cost: 80,
+    multiplier: 5.0,
+  },
+
+  // ── Combat multipliers ──────────────────────────────────────────────────────
+  {
+    id: "echo_combat_1",
+    name: "Battle-Hardened",
+    description: "Memories of countless battles harden your adventurers, increasing party DPS by 25%.",
+    category: "combat",
+    cost: 5,
+    multiplier: 1.25,
+  },
+  {
+    id: "echo_combat_2",
+    name: "Veteran's Edge",
+    description: "Veterans of transcendence know how to fight smarter, boosting party DPS by 50%.",
+    category: "combat",
+    cost: 15,
+    multiplier: 1.5,
+  },
+  {
+    id: "echo_combat_3",
+    name: "Transcendent Warrior",
+    description: "Your warriors carry the strength of every fallen timeline, doubling party DPS.",
+    category: "combat",
+    cost: 35,
+    multiplier: 2.0,
+  },
+
+  // ── Prestige threshold reductions ──────────────────────────────────────────
+  {
+    id: "echo_prestige_threshold_1",
+    name: "Accelerated Path",
+    description: "Experience from past lives shortens the road to prestige — threshold reduced by 10%.",
+    category: "prestige_threshold",
+    cost: 8,
+    multiplier: 0.9,
+  },
+  {
+    id: "echo_prestige_threshold_2",
+    name: "Shortcut Through Time",
+    description: "You've walked this path so many times you know every shortcut — threshold reduced by 20%.",
+    category: "prestige_threshold",
+    cost: 20,
+    multiplier: 0.8,
+  },
+
+  // ── Prestige runestone multipliers ─────────────────────────────────────────
+  {
+    id: "echo_prestige_runestones_1",
+    name: "Runic Attunement",
+    description: "Transcendent insight attunes you to the runestones, earning 50% more per prestige.",
+    category: "prestige_runestones",
+    cost: 8,
+    multiplier: 1.5,
+  },
+  {
+    id: "echo_prestige_runestones_2",
+    name: "Master Runesmith",
+    description: "You have mastered the art of runestone crafting, doubling your prestige runestone yield.",
+    category: "prestige_runestones",
+    cost: 20,
+    multiplier: 2.0,
+  },
+
+  // ── Echo meta multipliers ───────────────────────────────────────────────────
+  {
+    id: "echo_meta_1",
+    name: "Resonant Awakening",
+    description: "Your transcendence resonates deeper, amplifying future echo yields by 25%.",
+    category: "echo_meta",
+    cost: 10,
+    multiplier: 1.25,
+  },
+  {
+    id: "echo_meta_2",
+    name: "Transcendent Loop",
+    description: "Each loop of existence makes the next more powerful — future echo yields +50%.",
+    category: "echo_meta",
+    cost: 25,
+    multiplier: 1.5,
+  },
+  {
+    id: "echo_meta_3",
+    name: "Infinite Spiral",
+    description: "You have mastered the infinite spiral of transcendence, doubling all future echo yields.",
+    category: "echo_meta",
+    cost: 50,
+    multiplier: 2.0,
+  },
+];

apps/api/src/index.ts

@@ -7,6 +7,7 @@ import { authRouter } from "./routes/auth.js";
 import { bossRouter } from "./routes/boss.js";
 import { gameRouter } from "./routes/game.js";
 import { prestigeRouter } from "./routes/prestige.js";
+import { transcendenceRouter } from "./routes/transcendence.js";
 import { profileRouter } from "./routes/profile.js";
 
 const app = new Hono();
@@ -26,6 +27,7 @@ app.route("/auth", authRouter);
 app.route("/game", gameRouter);
 app.route("/boss", bossRouter);
 app.route("/prestige", prestigeRouter);
+app.route("/transcendence", transcendenceRouter);
 app.route("/profile", profileRouter);
 
 app.get("/health", (context) => context.json({ status: "ok" }));

apps/api/src/routes/boss.ts

@@ -59,7 +59,8 @@ const calculatePartyStats = (
     partyMaxHp += adventurer.level * 50 * adventurer.count;
   }
 
-  partyDPS *= equipmentCombatMultiplier * setCombatMultiplier;
+  const echoCombatMultiplier = state.transcendence?.echoCombatMultiplier ?? 1;
+  partyDPS *= equipmentCombatMultiplier * setCombatMultiplier * echoCombatMultiplier;
 
   return { partyDPS, partyMaxHp };
 };

apps/api/src/routes/game.ts

@@ -290,7 +290,19 @@ const validateAndSanitize = (incoming: GameState, previous: GameState): GameStat
   const prestige =
     incoming.prestige.count < previous.prestige.count ? previous.prestige : incoming.prestige;
 
-  return { ...incoming, resources, bosses, quests, achievements, prestige };
+  // Echoes are only granted server-side via transcendence and can only decrease between
+  // saves (spent on echo upgrades). Cap at the previous value to block inflation.
+  const cappedEchoes = Math.min(
+    incoming.transcendence?.echoes ?? 0,
+    previous.transcendence?.echoes ?? 0,
+  );
+  const transcendenceSpread = incoming.transcendence
+    ? { transcendence: { ...incoming.transcendence, echoes: cappedEchoes } }
+    : previous.transcendence
+      ? { transcendence: previous.transcendence }
+      : {};
+
+  return { ...incoming, resources, bosses, quests, achievements, prestige, ...transcendenceSpread };
 };
 
 export const gameRouter = new Hono<HonoEnv>();

apps/api/src/routes/transcendence.ts

@@ -0,0 +1,140 @@
+import type { BuyEchoUpgradeRequest, GameState, TranscendenceRequest } from "@elysium/types";
+import { Hono } from "hono";
+import type { HonoEnv } from "../types/hono.js";
+import { prisma } from "../db/client.js";
+import { authMiddleware } from "../middleware/auth.js";
+import { DEFAULT_TRANSCENDENCE_UPGRADES } from "../data/transcendenceUpgrades.js";
+import {
+  buildPostTranscendenceState,
+  computeTranscendenceMultipliers,
+  isEligibleForTranscendence,
+} from "../services/transcendence.js";
+
+export const transcendenceRouter = new Hono<HonoEnv>();
+
+transcendenceRouter.use("*", authMiddleware);
+
+transcendenceRouter.post("/", async (context) => {
+  const discordId = context.get("discordId") as string;
+  const body = await context.req.json<TranscendenceRequest>();
+
+  const characterName = body.characterName?.trim();
+  if (!characterName) {
+    return context.json({ error: "characterName is required" }, 400);
+  }
+
+  const record = await prisma.gameState.findUnique({ where: { discordId } });
+  if (!record) {
+    return context.json({ error: "No save found" }, 404);
+  }
+
+  const state = record.state as unknown as GameState;
+
+  if (!isEligibleForTranscendence(state)) {
+    return context.json(
+      { error: "Not eligible for transcendence — defeat The Absolute One first" },
+      400,
+    );
+  }
+
+  const { newState, newTranscendenceData, echoesEarned } = buildPostTranscendenceState(
+    state,
+    characterName,
+  );
+
+  // Capture current-run stats before the nuclear reset
+  const runBossesDefeated = state.bosses.filter((b) => b.status === "defeated").length;
+  const runQuestsCompleted = state.quests.filter((q) => q.status === "completed").length;
+  const runAdventurersRecruited = state.adventurers.reduce((sum, a) => sum + a.count, 0);
+  const runAchievementsUnlocked = (state.achievements ?? []).filter((a) => a.unlockedAt !== null).length;
+
+  const now = Date.now();
+  await prisma.gameState.update({
+    where: { discordId },
+    data: { state: newState as object, updatedAt: now },
+  });
+
+  await prisma.player.update({
+    where: { discordId },
+    data: {
+      characterName,
+      // Reset current-run counters (same as prestige)
+      totalGoldEarned: 0,
+      totalClicks: 0,
+      // Accumulate into lifetime totals
+      lifetimeGoldEarned: { increment: state.player.totalGoldEarned },
+      lifetimeClicks: { increment: state.player.totalClicks },
+      lifetimeBossesDefeated: { increment: runBossesDefeated },
+      lifetimeQuestsCompleted: { increment: runQuestsCompleted },
+      lifetimeAdventurersRecruited: { increment: runAdventurersRecruited },
+      lifetimeAchievementsUnlocked: { increment: runAchievementsUnlocked },
+      lastSavedAt: now,
+    },
+  });
+
+  return context.json({
+    echoes: echoesEarned,
+    newTranscendenceCount: newTranscendenceData.count,
+  });
+});
+
+transcendenceRouter.post("/buy-upgrade", async (context) => {
+  const discordId = context.get("discordId") as string;
+  const body = await context.req.json<BuyEchoUpgradeRequest>();
+
+  const { upgradeId } = body;
+  if (!upgradeId) {
+    return context.json({ error: "upgradeId is required" }, 400);
+  }
+
+  const upgrade = DEFAULT_TRANSCENDENCE_UPGRADES.find((u) => u.id === upgradeId);
+  if (!upgrade) {
+    return context.json({ error: "Unknown echo upgrade" }, 404);
+  }
+
+  const record = await prisma.gameState.findUnique({ where: { discordId } });
+  if (!record) {
+    return context.json({ error: "No save found" }, 404);
+  }
+
+  const state = record.state as unknown as GameState;
+
+  if (!state.transcendence) {
+    return context.json({ error: "No transcendence data found" }, 400);
+  }
+
+  const { purchasedUpgradeIds, echoes } = state.transcendence;
+
+  if (purchasedUpgradeIds.includes(upgradeId)) {
+    return context.json({ error: "Upgrade already purchased" }, 400);
+  }
+
+  if (echoes < upgrade.cost) {
+    return context.json({ error: "Not enough echoes" }, 400);
+  }
+
+  const newEchoes = echoes - upgrade.cost;
+  const newPurchasedIds = [...purchasedUpgradeIds, upgradeId];
+  const newMultipliers = computeTranscendenceMultipliers(newPurchasedIds);
+
+  const newState: GameState = {
+    ...state,
+    transcendence: {
+      ...state.transcendence,
+      echoes: newEchoes,
+      purchasedUpgradeIds: newPurchasedIds,
+      ...newMultipliers,
+    },
+  };
+
+  await prisma.gameState.update({
+    where: { discordId },
+    data: { state: newState as object, updatedAt: Date.now() },
+  });
+
+  return context.json({
+    echoesRemaining: newEchoes,
+    purchasedUpgradeIds: newPurchasedIds,
+    ...newMultipliers,
+  });
+});

apps/api/src/services/prestige.ts

@@ -16,11 +16,13 @@ const MILESTONE_RUNESTONES_PER_INTERVAL = 25;
  * Calculates the gold threshold required for the next prestige.
  * Formula: BASE * SCALE_FACTOR^prestigeCount — each prestige makes the next threshold harder.
  */
-export const calculatePrestigeThreshold = (prestigeCount: number): number =>
+export const calculatePrestigeThreshold = (prestigeCount: number, thresholdMultiplier = 1): number =>
-  BASE_PRESTIGE_GOLD_THRESHOLD * Math.pow(THRESHOLD_SCALE_FACTOR, prestigeCount);
+  BASE_PRESTIGE_GOLD_THRESHOLD * Math.pow(THRESHOLD_SCALE_FACTOR, prestigeCount) * thresholdMultiplier;
 
-export const isEligibleForPrestige = (state: GameState): boolean =>
+export const isEligibleForPrestige = (state: GameState): boolean => {
-  state.player.totalGoldEarned >= calculatePrestigeThreshold(state.prestige.count);
+  const thresholdMultiplier = state.transcendence?.echoPrestigeThresholdMultiplier ?? 1;
+  return state.player.totalGoldEarned >= calculatePrestigeThreshold(state.prestige.count, thresholdMultiplier);
+};
 
 const getCategoryMultiplier = (
   purchasedUpgradeIds: string[],
@@ -52,12 +54,13 @@ export const calculateRunestones = (
   totalGoldEarned: number,
   prestigeCount: number,
   purchasedUpgradeIds: string[],
+  echoRunestoneMultiplier = 1,
 ): number => {
   const threshold = calculatePrestigeThreshold(prestigeCount);
   const base =
     Math.floor(Math.sqrt(totalGoldEarned / threshold)) * RUNESTONES_PER_PRESTIGE_LEVEL;
   const runestoneMult = getCategoryMultiplier(purchasedUpgradeIds, "runestones");
-  return Math.floor(base * runestoneMult);
+  return Math.floor(base * runestoneMult * echoRunestoneMultiplier);
 };
 
 /**
@@ -85,10 +88,12 @@ export const buildPostPrestigeState = (
   currentState: GameState,
   characterName: string,
 ): { newState: GameState; newPrestigeData: PrestigeData; runestonesEarned: number; milestoneRunestones: number } => {
+  const echoRunestoneMultiplier = currentState.transcendence?.echoPrestigeRunestoneMultiplier ?? 1;
   const runestonesEarned = calculateRunestones(
     currentState.player.totalGoldEarned,
     currentState.prestige.count,
     currentState.prestige.purchasedUpgradeIds,
+    echoRunestoneMultiplier,
   );
   const newPrestigeCount = currentState.prestige.count + 1;
   const { purchasedUpgradeIds } = currentState.prestige;
@@ -113,6 +118,8 @@ export const buildPostPrestigeState = (
     lastTickAt: Date.now(),
     // Codex lore persists across prestiges — players keep their discovered entries
     ...(currentState.codex ? { codex: currentState.codex } : {}),
+    // Transcendence data is permanent — never wiped by prestige
+    ...(currentState.transcendence ? { transcendence: currentState.transcendence } : {}),
   };
 
   return { newState, newPrestigeData, runestonesEarned, milestoneRunestones };

apps/api/src/services/transcendence.ts

@@ -0,0 +1,84 @@
+import type { GameState, TranscendenceData, TranscendenceUpgradeCategory } from "@elysium/types";
+import { INITIAL_GAME_STATE } from "../data/initialState.js";
+import { DEFAULT_TRANSCENDENCE_UPGRADES } from "../data/transcendenceUpgrades.js";
+
+/** ID of the boss that must be defeated to unlock transcendence */
+const FINAL_BOSS_ID = "the_absolute_one";
+
+/** Base constant used in the echo yield formula */
+const ECHO_FORMULA_CONSTANT = 853;
+
+const getCategoryMultiplier = (
+  purchasedIds: string[],
+  category: TranscendenceUpgradeCategory,
+): number =>
+  DEFAULT_TRANSCENDENCE_UPGRADES
+    .filter((u) => u.category === category && purchasedIds.includes(u.id))
+    .reduce((mult, u) => mult * u.multiplier, 1);
+
+export const computeTranscendenceMultipliers = (
+  purchasedUpgradeIds: string[],
+): Omit<TranscendenceData, "count" | "echoes" | "purchasedUpgradeIds"> => ({
+  echoIncomeMultiplier: getCategoryMultiplier(purchasedUpgradeIds, "income"),
+  echoCombatMultiplier: getCategoryMultiplier(purchasedUpgradeIds, "combat"),
+  echoPrestigeThresholdMultiplier: getCategoryMultiplier(purchasedUpgradeIds, "prestige_threshold"),
+  echoPrestigeRunestoneMultiplier: getCategoryMultiplier(purchasedUpgradeIds, "prestige_runestones"),
+  echoMetaMultiplier: getCategoryMultiplier(purchasedUpgradeIds, "echo_meta"),
+});
+
+/**
+ * Returns true when the player is eligible to transcend:
+ * they must have defeated the final boss at least once.
+ */
+export const isEligibleForTranscendence = (state: GameState): boolean =>
+  state.bosses.some((b) => b.id === FINAL_BOSS_ID && b.status === "defeated");
+
+/**
+ * Calculates echo yield for a transcendence.
+ * Formula: floor(CONSTANT / sqrt(prestigeCount)) × echoMetaMultiplier
+ * Fewer prestiges = more echoes (rewards efficient play).
+ * Minimum prestige count of 1 is enforced to avoid division by zero.
+ */
+export const calculateEchoes = (
+  prestigeCount: number,
+  echoMetaMultiplier: number,
+): number => {
+  const safeCount = Math.max(prestigeCount, 1);
+  return Math.floor((ECHO_FORMULA_CONSTANT / Math.sqrt(safeCount)) * echoMetaMultiplier);
+};
+
+/**
+ * Builds the new game state after a transcendence (nuclear reset).
+ * Wipes everything except codex, dailyChallenges, and transcendence data.
+ */
+export const buildPostTranscendenceState = (
+  currentState: GameState,
+  characterName: string,
+): { newState: GameState; newTranscendenceData: TranscendenceData; echoesEarned: number } => {
+  const previousTranscendence = currentState.transcendence;
+  const echoMetaMultiplier = previousTranscendence?.echoMetaMultiplier ?? 1;
+
+  const echoesEarned = calculateEchoes(currentState.prestige.count, echoMetaMultiplier);
+  const previousEchoes = previousTranscendence?.echoes ?? 0;
+  const newCount = (previousTranscendence?.count ?? 0) + 1;
+  const newPurchasedIds = previousTranscendence?.purchasedUpgradeIds ?? [];
+
+  const newTranscendenceData: TranscendenceData = {
+    count: newCount,
+    echoes: previousEchoes + echoesEarned,
+    purchasedUpgradeIds: newPurchasedIds,
+    ...computeTranscendenceMultipliers(newPurchasedIds),
+  };
+
+  const freshState = INITIAL_GAME_STATE(currentState.player, characterName);
+  const newState: GameState = {
+    ...freshState,
+    lastTickAt: Date.now(),
+    // Codex lore persists through all resets
+    ...(currentState.codex ? { codex: currentState.codex } : {}),
+    // Transcendence data is permanent
+    transcendence: newTranscendenceData,
+  };
+
+  return { newState, newTranscendenceData, echoesEarned };
+};

apps/web/src/api/client.ts

@@ -3,6 +3,8 @@ import type {
   AuthResponse,
   BossChallengeRequest,
   BossChallengeResponse,
+  BuyEchoUpgradeRequest,
+  BuyEchoUpgradeResponse,
   BuyPrestigeUpgradeRequest,
   BuyPrestigeUpgradeResponse,
   LoadResponse,
@@ -11,6 +13,8 @@ import type {
   PublicProfileResponse,
   SaveRequest,
   SaveResponse,
+  TranscendenceRequest,
+  TranscendenceResponse,
   UpdateProfileRequest,
   UpdateProfileResponse,
 } from "@elysium/types";
@@ -91,6 +95,20 @@ export const buyPrestigeUpgrade = async (
     body: JSON.stringify(body),
   });
 
+export const transcend = async (body: TranscendenceRequest): Promise<TranscendenceResponse> =>
+  request<TranscendenceResponse>("/transcendence", {
+    method: "POST",
+    body: JSON.stringify(body),
+  });
+
+export const buyEchoUpgrade = async (
+  body: BuyEchoUpgradeRequest,
+): Promise<BuyEchoUpgradeResponse> =>
+  request<BuyEchoUpgradeResponse>("/transcendence/buy-upgrade", {
+    method: "POST",
+    body: JSON.stringify(body),
+  });
+
 export const getPublicProfile = async (
   discordId: string,
 ): Promise<PublicProfileResponse> =>

apps/web/src/components/game/AboutPanel.tsx

@@ -59,6 +59,10 @@ const HOW_TO_PLAY = [
     title: "☁️ Cloud Saves",
     body: "Your progress is automatically saved to the cloud every 30 seconds whilst you play. You can also force a manual save at any time using the sync button in the resource bar. Your save is protected by HMAC validation to ensure data integrity.",
   },
+  {
+    title: "🌌 Transcendence",
+    body: "Transcendence is the ultimate prestige layer, unlocked by defeating The Absolute One (requires Prestige 90). Transcending performs a nuclear reset — wiping resources, prestige, runestones, upgrades, and equipment — but grants Echoes based on your prestige count (fewer prestiges = more Echoes). Echoes are permanent and survive all future resets. Spend them in the Echo Shop on lasting multipliers: passive income, combat power, prestige quality-of-life, and Echo meta upgrades that amplify future Echo yields.",
+  },
 ];
 
 const formatDate = (dateStr: string): string =>

apps/web/src/components/game/GameLayout.tsx

@@ -14,12 +14,13 @@ import { EditProfileModal } from "./EditProfileModal.js";
 import { EquipmentPanel } from "./EquipmentPanel.js";
 import { OfflineModal } from "./OfflineModal.js";
 import { PrestigePanel } from "./PrestigePanel.js";
+import { TranscendencePanel } from "./TranscendencePanel.js";
 import { QuestPanel } from "./QuestPanel.js";
 import { StatisticsPanel } from "./StatisticsPanel.js";
 import { UpgradePanel } from "./UpgradePanel.js";
 import { DailyChallengePanel } from "./DailyChallengePanel.js";
 
-type Tab = "adventurers" | "upgrades" | "quests" | "bosses" | "equipment" | "achievements" | "prestige" | "statistics" | "daily" | "codex" | "about";
+type Tab = "adventurers" | "upgrades" | "quests" | "bosses" | "equipment" | "achievements" | "prestige" | "transcendence" | "statistics" | "daily" | "codex" | "about";
 
 const BASE_TABS: { id: Tab; label: string }[] = [
   { id: "adventurers", label: "⚔️ Adventurers" },
@@ -29,6 +30,7 @@ const BASE_TABS: { id: Tab; label: string }[] = [
   { id: "equipment", label: "🗡️ Equipment" },
   { id: "achievements", label: "🏆 Achievements" },
   { id: "prestige", label: "⭐ Prestige" },
+  { id: "transcendence", label: "🌌 Transcendence" },
   { id: "statistics", label: "📊 Statistics" },
   { id: "daily", label: "📅 Daily" },
   { id: "codex", label: "📖 Codex" },
@@ -66,6 +68,7 @@ export const GameLayout = (): React.JSX.Element => {
         resources={state.resources}
         runestones={state.prestige.runestones}
         prestigeCount={state.prestige.count}
+        transcendenceCount={state.transcendence?.count ?? 0}
         profileUrl={profileUrl}
         onEditProfile={() => { setEditingProfile(true); }}
         lastSavedAt={lastSavedAt}
@@ -112,6 +115,7 @@ export const GameLayout = (): React.JSX.Element => {
             {activeTab === "equipment" && <EquipmentPanel />}
             {activeTab === "achievements" && <AchievementPanel />}
             {activeTab === "prestige" && <PrestigePanel />}
+            {activeTab === "transcendence" && <TranscendencePanel />}
             {activeTab === "statistics" && <StatisticsPanel />}
             {activeTab === "daily" && <DailyChallengePanel />}
             {activeTab === "codex" && <CodexPanel />}

apps/web/src/components/game/TranscendencePanel.tsx

@@ -0,0 +1,224 @@
+import type { TranscendenceUpgradeCategory } from "@elysium/types";
+import { useState } from "react";
+import { useGame } from "../../context/GameContext.js";
+import {
+  TRANSCENDENCE_UPGRADES,
+  TRANSCENDENCE_UPGRADE_CATEGORY_LABELS,
+} from "../../data/transcendenceUpgrades.js";
+
+const ECHO_FORMULA_CONSTANT = 853;
+const FINAL_BOSS_ID = "the_absolute_one";
+
+const calculateEchoPreview = (prestigeCount: number, echoMetaMultiplier: number): number => {
+  const safeCount = Math.max(prestigeCount, 1);
+  return Math.floor((ECHO_FORMULA_CONSTANT / Math.sqrt(safeCount)) * echoMetaMultiplier);
+};
+
+const CATEGORY_ORDER: TranscendenceUpgradeCategory[] = [
+  "income",
+  "combat",
+  "prestige_threshold",
+  "prestige_runestones",
+  "echo_meta",
+];
+
+export const TranscendencePanel = (): React.JSX.Element => {
+  const { state, formatNumber, transcend, buyEchoUpgrade } = useGame();
+  const [characterName, setCharacterName] = useState("");
+  const [isPending, setIsPending] = useState(false);
+  const [result, setResult] = useState<{ echoes: number; count: number } | null>(null);
+  const [error, setError] = useState<string | null>(null);
+  const [buyingId, setBuyingId] = useState<string | null>(null);
+  const [activeTab, setActiveTab] = useState<"transcend" | "shop">("transcend");
+
+  if (!state) return <section className="panel"><p>Loading...</p></section>;
+
+  const { bosses, prestige: prestigeData, transcendence } = state;
+  const hasDefeatedFinalBoss = bosses.some((b) => b.id === FINAL_BOSS_ID && b.status === "defeated");
+  const echoMetaMultiplier = transcendence?.echoMetaMultiplier ?? 1;
+  const echoPreview = calculateEchoPreview(prestigeData.count, echoMetaMultiplier);
+  const currentEchoes = transcendence?.echoes ?? 0;
+  const transcendenceCount = transcendence?.count ?? 0;
+
+  const handleTranscend = async (): Promise<void> => {
+    if (!characterName.trim()) return;
+    setIsPending(true);
+    setError(null);
+    try {
+      const data = await transcend(characterName.trim());
+      setResult({ echoes: data.echoes, count: data.newTranscendenceCount });
+    } catch (err) {
+      setError(err instanceof Error ? err.message : "Transcendence failed");
+    } finally {
+      setIsPending(false);
+    }
+  };
+
+  const handleBuyUpgrade = async (upgradeId: string): Promise<void> => {
+    setBuyingId(upgradeId);
+    try {
+      await buyEchoUpgrade(upgradeId);
+    } finally {
+      setBuyingId(null);
+    }
+  };
+
+  const upgradesByCategory = CATEGORY_ORDER.map((category) => ({
+    category,
+    label: TRANSCENDENCE_UPGRADE_CATEGORY_LABELS[category] ?? category,
+    upgrades: TRANSCENDENCE_UPGRADES.filter((u) => u.category === category),
+  }));
+
+  return (
+    <section className="panel transcendence-panel">
+      <h2>🌌 Transcendence</h2>
+
+      <div className="prestige-tabs">
+        <button
+          className={`prestige-tab ${activeTab === "transcend" ? "active" : ""}`}
+          onClick={() => { setActiveTab("transcend"); }}
+          type="button"
+        >
+          Transcend
+        </button>
+        <button
+          className={`prestige-tab ${activeTab === "shop" ? "active" : ""}`}
+          onClick={() => { setActiveTab("shop"); }}
+          type="button"
+        >
+          ✨ Echo Shop ({formatNumber(currentEchoes)} echoes)
+        </button>
+      </div>
+
+      {activeTab === "transcend" && (
+        <>
+          <p className="transcendence-intro">
+            Transcendence is the ultimate reset. It wipes{" "}
+            <strong>everything</strong> — resources, prestige, runestones, upgrades,
+            and equipment — but grants <strong>Echoes</strong>, a permanent currency
+            that survives all future resets. Echoes power upgrades that permanently
+            amplify every run from this point forward.
+          </p>
+          <p className="transcendence-intro">
+            <em>
+              Fewer prestiges = more Echoes. Optimise your run for maximum yield!
+            </em>
+          </p>
+
+          <div className="transcendence-status">
+            {transcendenceCount > 0 && (
+              <p>Transcendence count: <strong>{transcendenceCount}</strong></p>
+            )}
+            <p>Current Echoes: <strong>{formatNumber(currentEchoes)}</strong></p>
+            <p>Current prestige count: <strong>{prestigeData.count}</strong></p>
+            {hasDefeatedFinalBoss && (
+              <p className="echo-preview">
+                Echoes on transcendence: <strong>+{formatNumber(echoPreview)}</strong>
+                {echoMetaMultiplier > 1 && (
+                  <span className="echo-meta-bonus">
+                    {" "}(×{echoMetaMultiplier.toFixed(2)} meta bonus applied)
+                  </span>
+                )}
+              </p>
+            )}
+          </div>
+
+          {!hasDefeatedFinalBoss && (
+            <div className="transcendence-locked">
+              <p>🔒 <strong>Defeat The Absolute One</strong> to unlock transcendence.</p>
+              <p className="transcendence-hint">
+                The Absolute One is the final boss of The Absolute zone, requiring
+                Prestige 90 to challenge.
+              </p>
+            </div>
+          )}
+
+          {hasDefeatedFinalBoss && (
+            <div className="prestige-form">
+              <p>You are ready to transcend. This action is <strong>irreversible</strong>.</p>
+              <p>Choose your new character name for the next cycle:</p>
+              <input
+                disabled={isPending}
+                maxLength={32}
+                onChange={(e) => { setCharacterName(e.target.value); }}
+                placeholder="Character name..."
+                type="text"
+                value={characterName}
+              />
+              <button
+                className="transcendence-button"
+                disabled={isPending || !characterName.trim()}
+                onClick={() => { void handleTranscend(); }}
+                type="button"
+              >
+                {isPending
+                  ? "Transcending..."
+                  : `🌌 Transcend (+${formatNumber(echoPreview)} Echoes)`}
+              </button>
+              {error && <p className="error">{error}</p>}
+              {result && (
+                <p className="success">
+                  Transcended! Earned{" "}
+                  <strong>{formatNumber(result.echoes)} Echoes</strong>. This is
+                  Transcendence {result.count}. A new cycle begins.
+                </p>
+              )}
+            </div>
+          )}
+        </>
+      )}
+
+      {activeTab === "shop" && (
+        <div className="echo-shop">
+          <p className="shop-balance">
+            Balance: <strong>{formatNumber(currentEchoes)} Echoes</strong>
+          </p>
+          <p className="echo-shop-description">
+            Echo upgrades are <strong>permanent</strong> — they survive all future
+            prestiges and transcendences.
+          </p>
+
+          {upgradesByCategory.map(({ category, label, upgrades }) => (
+            <div key={category} className="shop-category">
+              <h3>{label}</h3>
+              <div className="shop-upgrades">
+                {upgrades.map((upgrade) => {
+                  const purchased = (transcendence?.purchasedUpgradeIds ?? []).includes(upgrade.id);
+                  const canAfford = currentEchoes >= upgrade.cost;
+                  const isLoading = buyingId === upgrade.id;
+
+                  return (
+                    <div
+                      key={upgrade.id}
+                      className={`shop-upgrade-card echo-upgrade-card ${purchased ? "purchased" : ""} ${!canAfford && !purchased ? "unaffordable" : ""}`}
+                    >
+                      <div className="shop-upgrade-info">
+                        <h4>{upgrade.name}</h4>
+                        <p>{upgrade.description}</p>
+                        <p className="upgrade-cost">
+                          {purchased
+                            ? "✅ Purchased"
+                            : `✨ ${formatNumber(upgrade.cost)} Echoes`}
+                        </p>
+                      </div>
+                      {!purchased && (
+                        <button
+                          className="buy-upgrade-button echo-buy-button"
+                          disabled={!canAfford || isLoading || buyingId !== null}
+                          onClick={() => { void handleBuyUpgrade(upgrade.id); }}
+                          type="button"
+                        >
+                          {isLoading ? "Buying..." : "Buy"}
+                        </button>
+                      )}
+                    </div>
+                  );
+                })}
+              </div>
+            </div>
+          ))}
+        </div>
+      )}
+    </section>
+  );
+};

apps/web/src/components/ui/ResourceBar.tsx

@@ -6,6 +6,7 @@ interface ResourceBarProps {
   resources: Resource;
   runestones: number;
   prestigeCount: number;
+  transcendenceCount: number;
   profileUrl: string;
   onEditProfile: () => void;
   lastSavedAt: number | null;
@@ -29,6 +30,7 @@ export const ResourceBar = ({
   resources,
   runestones,
   prestigeCount,
+  transcendenceCount,
   profileUrl,
   onEditProfile,
   lastSavedAt,
@@ -63,6 +65,11 @@ export const ResourceBar = ({
       <span className="resource-value">{formatNumber(runestones)}</span>
       <span className="resource-label">Runestones</span>
     </div>
+    {transcendenceCount > 0 && (
+      <div className="transcendence-badge">
+        🌌 Transcendence {transcendenceCount}
+      </div>
+    )}
     {prestigeCount > 0 && (
       <div className="prestige-badge">
         ⭐ Prestige {prestigeCount}

apps/web/src/context/GameContext.tsx

@@ -8,11 +8,13 @@ import {
   useState,
 } from "react";
 import {
+  buyEchoUpgrade as buyEchoUpgradeApi,
   buyPrestigeUpgrade as buyPrestigeUpgradeApi,
   challengeBoss as challengeBossApi,
   loadGame,
   prestige as prestigeApi,
   saveGame,
+  transcend as transcendApi,
 } from "../api/client.js";
 import { CODEX_ENTRIES } from "../data/codex.js";
 import { RESOURCE_CAP, applyTick, calculateClickPower } from "../engine/tick.js";
@@ -81,6 +83,10 @@ interface GameContextValue {
   newCodexEntryIds: string[];
   /** Remove a codex entry ID from the notification queue */
   dismissCodexEntry: (id: string) => void;
+  /** Perform a transcendence — nuclear reset, earning echoes */
+  transcend: (characterName: string) => Promise<{ echoes: number; newTranscendenceCount: number }>;
+  /** Buy an echo upgrade from the transcendence shop */
+  buyEchoUpgrade: (upgradeId: string) => Promise<void>;
 }
 
 const GameContext = createContext<GameContextValue | null>(null);
@@ -531,6 +537,36 @@ export const GameProvider = ({ children }: { children: React.ReactNode }): React
     }
   }, []);
 
+  const transcend = useCallback(async (characterName: string) => {
+    const result = await transcendApi({ characterName });
+    await reload();
+    return result;
+  }, [reload]);
+
+  const buyEchoUpgrade = useCallback(async (upgradeId: string) => {
+    try {
+      const result = await buyEchoUpgradeApi({ upgradeId });
+      setState((prev) => {
+        if (!prev || !prev.transcendence) return prev;
+        return {
+          ...prev,
+          transcendence: {
+            ...prev.transcendence,
+            echoes: result.echoesRemaining,
+            purchasedUpgradeIds: result.purchasedUpgradeIds,
+            echoIncomeMultiplier: result.echoIncomeMultiplier,
+            echoCombatMultiplier: result.echoCombatMultiplier,
+            echoPrestigeThresholdMultiplier: result.echoPrestigeThresholdMultiplier,
+            echoPrestigeRunestoneMultiplier: result.echoPrestigeRunestoneMultiplier,
+            echoMetaMultiplier: result.echoMetaMultiplier,
+          },
+        };
+      });
+    } catch {
+      // Silently ignore server errors
+    }
+  }, []);
+
   const toggleAutoPrestige = useCallback(() => {
     setState((prev) => {
       if (!prev) return prev;
@@ -713,6 +749,8 @@ export const GameProvider = ({ children }: { children: React.ReactNode }): React
         toggleAutoPrestige,
         newCodexEntryIds,
         dismissCodexEntry,
+        transcend,
+        buyEchoUpgrade,
       }}
     >
       {children}

apps/web/src/data/transcendenceUpgrades.ts

@@ -0,0 +1,142 @@
+import type { TranscendenceUpgrade } from "@elysium/types";
+
+export const DEFAULT_TRANSCENDENCE_UPGRADES: TranscendenceUpgrade[] = [
+  // ── Income multipliers ──────────────────────────────────────────────────────
+  {
+    id: "echo_income_1",
+    name: "Whisper of Power",
+    description: "The echoes of past runs linger, amplifying your guild's income by 25%.",
+    category: "income",
+    cost: 5,
+    multiplier: 1.25,
+  },
+  {
+    id: "echo_income_2",
+    name: "Resonance",
+    description: "Your transcendent experience resonates through your guild, boosting income by 50%.",
+    category: "income",
+    cost: 10,
+    multiplier: 1.5,
+  },
+  {
+    id: "echo_income_3",
+    name: "Harmonic Surge",
+    description: "The harmony of multiple timelines surges through your guild, doubling its income.",
+    category: "income",
+    cost: 20,
+    multiplier: 2.0,
+  },
+  {
+    id: "echo_income_4",
+    name: "Ethereal Overflow",
+    description: "Ethereal energy overflows from your transcendence, tripling your guild's income.",
+    category: "income",
+    cost: 40,
+    multiplier: 3.0,
+  },
+  {
+    id: "echo_income_5",
+    name: "Infinite Chorus",
+    description: "The infinite chorus of every run you've ever played amplifies your guild fivefold.",
+    category: "income",
+    cost: 80,
+    multiplier: 5.0,
+  },
+
+  // ── Combat multipliers ──────────────────────────────────────────────────────
+  {
+    id: "echo_combat_1",
+    name: "Battle-Hardened",
+    description: "Memories of countless battles harden your adventurers, increasing party DPS by 25%.",
+    category: "combat",
+    cost: 5,
+    multiplier: 1.25,
+  },
+  {
+    id: "echo_combat_2",
+    name: "Veteran's Edge",
+    description: "Veterans of transcendence know how to fight smarter, boosting party DPS by 50%.",
+    category: "combat",
+    cost: 15,
+    multiplier: 1.5,
+  },
+  {
+    id: "echo_combat_3",
+    name: "Transcendent Warrior",
+    description: "Your warriors carry the strength of every fallen timeline, doubling party DPS.",
+    category: "combat",
+    cost: 35,
+    multiplier: 2.0,
+  },
+
+  // ── Prestige threshold reductions ──────────────────────────────────────────
+  {
+    id: "echo_prestige_threshold_1",
+    name: "Accelerated Path",
+    description: "Experience from past lives shortens the road to prestige — threshold reduced by 10%.",
+    category: "prestige_threshold",
+    cost: 8,
+    multiplier: 0.9,
+  },
+  {
+    id: "echo_prestige_threshold_2",
+    name: "Shortcut Through Time",
+    description: "You've walked this path so many times you know every shortcut — threshold reduced by 20%.",
+    category: "prestige_threshold",
+    cost: 20,
+    multiplier: 0.8,
+  },
+
+  // ── Prestige runestone multipliers ─────────────────────────────────────────
+  {
+    id: "echo_prestige_runestones_1",
+    name: "Runic Attunement",
+    description: "Transcendent insight attunes you to the runestones, earning 50% more per prestige.",
+    category: "prestige_runestones",
+    cost: 8,
+    multiplier: 1.5,
+  },
+  {
+    id: "echo_prestige_runestones_2",
+    name: "Master Runesmith",
+    description: "You have mastered the art of runestone crafting, doubling your prestige runestone yield.",
+    category: "prestige_runestones",
+    cost: 20,
+    multiplier: 2.0,
+  },
+
+  // ── Echo meta multipliers ───────────────────────────────────────────────────
+  {
+    id: "echo_meta_1",
+    name: "Resonant Awakening",
+    description: "Your transcendence resonates deeper, amplifying future echo yields by 25%.",
+    category: "echo_meta",
+    cost: 10,
+    multiplier: 1.25,
+  },
+  {
+    id: "echo_meta_2",
+    name: "Transcendent Loop",
+    description: "Each loop of existence makes the next more powerful — future echo yields +50%.",
+    category: "echo_meta",
+    cost: 25,
+    multiplier: 1.5,
+  },
+  {
+    id: "echo_meta_3",
+    name: "Infinite Spiral",
+    description: "You have mastered the infinite spiral of transcendence, doubling all future echo yields.",
+    category: "echo_meta",
+    cost: 50,
+    multiplier: 2.0,
+  },
+];
+export const TRANSCENDENCE_UPGRADES = DEFAULT_TRANSCENDENCE_UPGRADES;
+
+export const TRANSCENDENCE_UPGRADE_CATEGORY_LABELS: Record<string, string> = {
+  income: "✨ Income Multipliers",
+  combat: "⚔️ Combat Multipliers",
+  prestige_threshold: "🎯 Prestige Quality of Life — Threshold",
+  prestige_runestones: "🔮 Prestige Quality of Life — Runestones",
+  echo_meta: "🌌 Echo Meta Upgrades",
+};

apps/web/src/engine/tick.ts

@@ -64,6 +64,7 @@ export const applyTick = (state: GameState, deltaSeconds: number): GameState =>
   const runestonesIncome = state.prestige.runestonesIncomeMultiplier ?? 1;
   const runestonesEssence = state.prestige.runestonesEssenceMultiplier ?? 1;
   const runestonesCrystal = state.prestige.runestonesCrystalMultiplier ?? 1;
+  const echoIncome = state.transcendence?.echoIncomeMultiplier ?? 1;
 
   let goldGained = 0;
   let essenceGained = 0;
@@ -90,6 +91,7 @@ export const applyTick = (state: GameState, deltaSeconds: number): GameState =>
       upgradeMultiplier *
       prestige *
       runestonesIncome *
+      echoIncome *
       equipmentGoldMultiplier *
       setGoldMultiplier *
       deltaSeconds;
@@ -282,12 +284,14 @@ export const calculateClickPower = (state: GameState): number => {
   const setClickMultiplier = computeSetBonuses(equippedItems.map((e) => e.id), EQUIPMENT_SETS).clickMultiplier;
 
   const runestonesClick = state.prestige.runestonesClickMultiplier ?? 1;
+  const echoIncome = state.transcendence?.echoIncomeMultiplier ?? 1;
 
   return (
     state.baseClickPower *
     clickMultiplier *
     state.prestige.productionMultiplier *
     runestonesClick *
+    echoIncome *
     equipmentClickMultiplier *
     setClickMultiplier
   );

apps/web/src/styles.css

@@ -2320,3 +2320,124 @@ body {
   text-align: center;
   vertical-align: middle;
 }
+
+
+/* ── Transcendence ─────────────────────────────────────────────────────── */
+
+.transcendence-badge {
+  background: linear-gradient(135deg, #4c1d95, #7c3aed);
+  border-radius: 999px;
+  font-size: 0.85rem;
+  font-weight: 600;
+  padding: 0.25rem 0.75rem;
+}
+
+.transcendence-panel .transcendence-intro {
+  color: var(--colour-text-muted);
+  font-size: 0.95rem;
+  margin-bottom: 0.75rem;
+}
+
+.transcendence-status {
+  background: var(--colour-surface);
+  border: 1px solid #7c3aed;
+  border-radius: var(--radius);
+  margin: 1rem 0;
+  padding: 1rem;
+}
+
+.transcendence-status p {
+  margin: 0.25rem 0;
+}
+
+.echo-preview {
+  color: #a78bfa;
+  font-weight: 600;
+  margin-top: 0.5rem !important;
+}
+
+.echo-meta-bonus {
+  color: var(--colour-text-muted);
+  font-size: 0.85rem;
+  font-weight: 400;
+}
+
+.transcendence-locked {
+  background: rgba(124, 58, 237, 0.1);
+  border: 1px solid #7c3aed;
+  border-radius: var(--radius);
+  padding: 1rem;
+  text-align: center;
+}
+
+.transcendence-hint {
+  color: var(--colour-text-muted);
+  font-size: 0.85rem;
+  margin-top: 0.5rem;
+}
+
+.transcendence-button {
+  background: linear-gradient(135deg, #4c1d95, #7c3aed);
+  border: none;
+  border-radius: var(--radius);
+  color: #fff;
+  cursor: pointer;
+  font-size: 1rem;
+  font-weight: 700;
+  margin-top: 0.5rem;
+  padding: 0.75rem 2rem;
+  transition: opacity 0.2s;
+  width: 100%;
+}
+
+.transcendence-button:hover:not(:disabled) {
+  opacity: 0.85;
+}
+
+.transcendence-button:disabled {
+  cursor: not-allowed;
+  opacity: 0.4;
+}
+
+.echo-shop {
+  display: flex;
+  flex-direction: column;
+  gap: 1rem;
+}
+
+.echo-shop-description {
+  color: var(--colour-text-muted);
+  font-size: 0.9rem;
+  margin: 0;
+}
+
+.echo-upgrade-card {
+  border-color: #7c3aed !important;
+}
+
+.echo-upgrade-card.purchased {
+  border-color: #6d28d9 !important;
+  opacity: 0.7;
+}
+
+.echo-buy-button {
+  background: linear-gradient(135deg, #4c1d95, #7c3aed);
+  border: none;
+  border-radius: var(--radius);
+  color: #fff;
+  cursor: pointer;
+  font-size: 0.875rem;
+  font-weight: 600;
+  padding: 0.5rem 1rem;
+  transition: opacity 0.2s;
+  white-space: nowrap;
+}
+
+.echo-buy-button:hover:not(:disabled) {
+  opacity: 0.85;
+}
+
+.echo-buy-button:disabled {
+  cursor: not-allowed;
+  opacity: 0.4;
+}

packages/types/src/index.ts

@@ -12,6 +12,8 @@ export type {
   AuthResponse,
   BossChallengeRequest,
   BossChallengeResponse,
+  BuyEchoUpgradeRequest,
+  BuyEchoUpgradeResponse,
   BuyPrestigeUpgradeRequest,
   BuyPrestigeUpgradeResponse,
   GiteaRelease,
@@ -21,6 +23,8 @@ export type {
   PublicProfileResponse,
   SaveRequest,
   SaveResponse,
+  TranscendenceRequest,
+  TranscendenceResponse,
   UpdateProfileRequest,
   UpdateProfileResponse,
 } from "./interfaces/Api.js";
@@ -59,3 +63,8 @@ export type {
 export type { Zone, ZoneStatus } from "./interfaces/Zone.js";
 export type { NumberFormat, ProfileSettings } from "./interfaces/ProfileSettings.js";
 export { DEFAULT_PROFILE_SETTINGS } from "./interfaces/ProfileSettings.js";
+export type {
+  TranscendenceData,
+  TranscendenceUpgrade,
+  TranscendenceUpgradeCategory,
+} from "./interfaces/Transcendence.js";

packages/types/src/interfaces/Api.ts

@@ -127,6 +127,29 @@ export interface UpdateProfileResponse {
   profileSettings: ProfileSettings;
 }
 
+export interface TranscendenceRequest {
+  characterName: string;
+}
+
+export interface TranscendenceResponse {
+  echoes: number;
+  newTranscendenceCount: number;
+}
+
+export interface BuyEchoUpgradeRequest {
+  upgradeId: string;
+}
+
+export interface BuyEchoUpgradeResponse {
+  echoesRemaining: number;
+  purchasedUpgradeIds: string[];
+  echoIncomeMultiplier: number;
+  echoCombatMultiplier: number;
+  echoPrestigeThresholdMultiplier: number;
+  echoPrestigeRunestoneMultiplier: number;
+  echoMetaMultiplier: number;
+}
+
 export interface ApiError {
   error: string;
 }

packages/types/src/interfaces/GameState.ts

@@ -3,6 +3,7 @@ import type { Adventurer } from "./Adventurer.js";
 import type { Boss } from "./Boss.js";
 import type { CodexState } from "./Codex.js";
 import type { DailyChallengeState } from "./DailyChallenge.js";
+import type { TranscendenceData } from "./Transcendence.js";
 import type { Equipment } from "./Equipment.js";
 import type { Player } from "./Player.js";
 import type { PrestigeData } from "./Prestige.js";
@@ -30,4 +31,6 @@ export interface GameState {
   dailyChallenges?: DailyChallengeState;
   /** Lore codex unlock state — optional for backwards compatibility with old saves */
   codex?: CodexState;
+  /** Transcendence (second prestige layer) state — optional for backwards compatibility */
+  transcendence?: TranscendenceData;
 }

packages/types/src/interfaces/Transcendence.ts

@@ -0,0 +1,36 @@
+export type TranscendenceUpgradeCategory =
+  | "income"
+  | "combat"
+  | "prestige_threshold"
+  | "prestige_runestones"
+  | "echo_meta";
+
+export interface TranscendenceUpgrade {
+  id: string;
+  name: string;
+  description: string;
+  category: TranscendenceUpgradeCategory;
+  /** Echo cost to purchase */
+  cost: number;
+  /** Multiplicative effect of this upgrade */
+  multiplier: number;
+}
+
+export interface TranscendenceData {
+  /** Number of times the player has transcended */
+  count: number;
+  /** Echoes accumulated across all transcendences */
+  echoes: number;
+  /** IDs of echo upgrades purchased with echoes */
+  purchasedUpgradeIds: string[];
+  /** Pre-computed: multiplier applied to all passive gold income */
+  echoIncomeMultiplier: number;
+  /** Pre-computed: multiplier applied to party DPS in boss fights */
+  echoCombatMultiplier: number;
+  /** Pre-computed: multiplier applied to the prestige gold threshold (< 1 lowers requirement) */
+  echoPrestigeThresholdMultiplier: number;
+  /** Pre-computed: multiplier applied to runestones earned per prestige */
+  echoPrestigeRunestoneMultiplier: number;
+  /** Pre-computed: multiplier applied to echo yield on future transcendences */
+  echoMetaMultiplier: number;
+}