feat: Sprint 3 — Prestige Loop endless

- Migration saves: saveVersion pattern + migrateSave lazy (v1→v2)
- Formule ADN rebalancée: log10 + clamp min 1 + cap bonus ×4
- Prestige Experience: modal fullscreen, preview ADN, stats run, best run
- Arbre V2: 25 nœuds, 3 capstones, post-capstones repeatables (scaling par tranche)
- Convergence évolutif Alpha→Omega (tier system)
- Reset arbre: 1 gratuit/prestige, payant linéaire au-delà
- Milestones prestige: 8 paliers (1→100), cosmétiques exclusifs, bonus gameplay
- balance.ts: constantes centralisées pour playtest
- 136 tests green, 0 regression

Backend/database/migrations/003_save_version.sql

@@ -0,0 +1,4 @@
+-- Migration 003: Add save_version column for Sprint 3 migration system
+-- Safe to run on existing data — defaults to 1 (Sprint 2 saves)
+
+ALTER TABLE game_saves ADD COLUMN save_version INT DEFAULT 1 AFTER game_state;

Backend/database/schema.sql

@@ -16,6 +16,7 @@ CREATE TABLE game_saves (
   id INT AUTO_INCREMENT PRIMARY KEY,
   user_id INT NOT NULL UNIQUE,
   game_state JSON NOT NULL,
+  save_version INT DEFAULT 1,
   last_save TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
   lifetime_tadpoles BIGINT DEFAULT 0,
   prestige_count INT DEFAULT 0,

Backend/src/controllers/saveControllers.js

@@ -1,4 +1,5 @@
 const tables = require("../tables");
+const { migrateSave } = require("../services/migrateSave");
 
 // --- Anti-cheat validation ---
 
@@ -75,11 +76,14 @@ const load = async (req, res) => {
     }
 
     // game_state est stocké en JSON — MySQL le retourne comme objet si type JSON
-    const gameState =
+    const rawState =
       typeof save.game_state === "string"
         ? JSON.parse(save.game_state)
         : save.game_state;
 
+    // Migrate on load — lazy migration, never touch DB rows directly
+    const gameState = migrateSave(rawState);
+
     return res.status(200).json({
       gameState,
       lastSave: save.last_save,

Backend/src/models/GameSaveManager.js

@@ -15,18 +15,20 @@ class GameSaveManager extends AbstractManager {
 
   async upsert(userId, gameState, metadata) {
     const { lifetimeTadpoles, prestigeCount, playTimeSeconds } = metadata;
+    const saveVersion = gameState.saveVersion ?? 1;
     const gameStateJson = JSON.stringify(gameState);
 
     const [result] = await this.database.query(
-      `INSERT INTO ${this.table} (user_id, game_state, lifetime_tadpoles, prestige_count, play_time_seconds)
+      `INSERT INTO ${this.table} (user_id, game_state, save_version, lifetime_tadpoles, prestige_count, play_time_seconds)
-       VALUES (?, ?, ?, ?, ?)
+       VALUES (?, ?, ?, ?, ?, ?)
        ON DUPLICATE KEY UPDATE
          game_state = VALUES(game_state),
+         save_version = VALUES(save_version),
          lifetime_tadpoles = VALUES(lifetime_tadpoles),
          prestige_count = VALUES(prestige_count),
          play_time_seconds = VALUES(play_time_seconds),
          last_save = CURRENT_TIMESTAMP`,
-      [userId, gameStateJson, lifetimeTadpoles, prestigeCount, playTimeSeconds]
+      [userId, gameStateJson, saveVersion, lifetimeTadpoles, prestigeCount, playTimeSeconds]
     );
 
     return result.affectedRows;

Backend/src/services/migrateSave.js

@@ -0,0 +1,65 @@
+// migrateSave.js — Backend save migration (mirrors Frontend/src/core/migrateSave.ts)
+// Applied on load — lazy migration, never touch DB directly.
+
+const CURRENT_SAVE_VERSION = 2;
+
+// Default evolution tree (Sprint 2 — 18 nodes)
+// Used to merge new nodes into old saves
+const DEFAULT_TREE_IDS = [
+  "ponte_amelioree", "double_ponte", "ponte_frenetique", "auto_ponte",
+  "ponte_critique", "maitre_pondeur",
+  "instinct_gregaire", "symbiose_algale", "courant_profond", "maree_haute",
+  "ecosysteme_mature", "marais_eternel",
+  "memoire_genetique", "adn_renforce", "eveil_rapide", "resilience",
+  "heritage", "transcendance",
+];
+
+/**
+ * Migrate a raw game state to the current version.
+ * Backend only needs structural migration for anti-cheat validation —
+ * the full tree/generator merge happens on the frontend.
+ */
+function migrateSave(raw) {
+  if (!raw || typeof raw !== "object") return raw;
+
+  const version = typeof raw.saveVersion === "number" ? raw.saveVersion : 1;
+  let state = { ...raw };
+
+  if (version < 2) {
+    state = migrateV1toV2(state);
+  }
+
+  return state;
+}
+
+function migrateV1toV2(state) {
+  state.saveVersion = 2;
+
+  // RunStats
+  if (!state.runStats) {
+    state.runStats = {
+      startedAt: state.lastTick || Date.now(),
+      tadpolesProduced: 0,
+      bestRun: null,
+    };
+  }
+
+  // Tree reset fields
+  if (typeof state.freeResetAvailable !== "boolean") {
+    state.freeResetAvailable = true;
+  }
+  if (typeof state.extraResetsUsed !== "number") {
+    state.extraResetsUsed = 0;
+  }
+
+  // Backfill cosmetics
+  if (!state.lastOnline) state.lastOnline = state.lastTick;
+  if (!Array.isArray(state.cosmeticInventory)) state.cosmeticInventory = [];
+  if (!state.cosmeticEquipped || typeof state.cosmeticEquipped !== "object") {
+    state.cosmeticEquipped = {};
+  }
+
+  return state;
+}
+
+module.exports = { migrateSave, CURRENT_SAVE_VERSION };

Frontend/src/__tests__/balance.test.ts

@@ -0,0 +1,53 @@
+import { describe, it, expect } from "vitest";
+import { postCapstoneCost, treeResetCost } from "../core/balance";
+
+describe("postCapstoneCost", () => {
+  it("first purchase = base cost (no multiplier)", () => {
+    expect(postCapstoneCost(500, 0)).toBe(500);
+  });
+
+  it("applies ×1.5 for purchases 1-5", () => {
+    expect(postCapstoneCost(500, 1)).toBe(750);
+    expect(postCapstoneCost(500, 2)).toBe(Math.floor(500 * 1.5 * 1.5));
+  });
+
+  it("uses ×1.8 tier for purchases 5-9", () => {
+    const at5 = postCapstoneCost(500, 5);
+    const at6 = postCapstoneCost(500, 6);
+    // Ratio should be ~1.8 (floor rounding tolerance ±1)
+    expect(at6 / at5).toBeCloseTo(1.8, 1);
+  });
+
+  it("uses ×2.0 tier for purchases 10+", () => {
+    const at10 = postCapstoneCost(500, 10);
+    const at11 = postCapstoneCost(500, 11);
+    expect(at11 / at10).toBeCloseTo(2.0, 1);
+  });
+
+  it("cost always increases", () => {
+    let prev = 0;
+    for (let i = 0; i < 15; i++) {
+      const cost = postCapstoneCost(500, i);
+      expect(cost).toBeGreaterThan(prev);
+      prev = cost;
+    }
+  });
+});
+
+describe("treeResetCost", () => {
+  it("free reset costs 0", () => {
+    expect(treeResetCost(true, 0)).toBe(0);
+    expect(treeResetCost(true, 5)).toBe(0);
+  });
+
+  it("first paid reset costs 5 ADN", () => {
+    expect(treeResetCost(false, 0)).toBe(5);
+  });
+
+  it("scales linearly", () => {
+    expect(treeResetCost(false, 0)).toBe(5);
+    expect(treeResetCost(false, 1)).toBe(10);
+    expect(treeResetCost(false, 2)).toBe(15);
+    expect(treeResetCost(false, 3)).toBe(20);
+  });
+});

Frontend/src/__tests__/economy.test.ts

@@ -299,31 +299,51 @@ describe("computePrestigeDna", () => {
     expect(computePrestigeDna(0)).toBe(0);
   });
 
-  it("retourne 150 pour 1e9 têtards (sqrt(1) = 1)", () => {
+  it("retourne 0 sous le seuil de 1M", () => {
-    expect(computePrestigeDna(1e9)).toBe(150);
+    expect(computePrestigeDna(999_999)).toBe(0);
   });
 
-  it("retourne 212 pour 2e9 têtards (sqrt(2) ≈ 1.414)", () => {
+  it("retourne 1 (clamp) à exactement 1M têtards", () => {
-    expect(computePrestigeDna(2e9)).toBe(Math.floor(150 * Math.sqrt(2)));
+    expect(computePrestigeDna(1e6)).toBe(1);
   });
 
-  it("scaling sub-linéaire — 10× têtards ≠ 10× ADN", () => {
+  it("retourne 50 pour 10M têtards (log10(10) = 1)", () => {
-    const dna1 = computePrestigeDna(1e9);
+    expect(computePrestigeDna(10e6)).toBe(50);
-    const dna10 = computePrestigeDna(10e9);
+  });
-    expect(dna10 / dna1).toBeCloseTo(Math.sqrt(10), 1);
+
+  it("scaling log — 10M→100M donne 2× ADN (log10(100) = 2)", () => {
+    const dna10m = computePrestigeDna(10e6);
+    const dna100m = computePrestigeDna(100e6);
+    expect(dna100m / dna10m).toBeCloseTo(2, 1);
+  });
+
+  it("prestige bonus augmente le gain (+5% par prestige)", () => {
+    const base = computePrestigeDna(10e6, 0);
+    const with10 = computePrestigeDna(10e6, 10);
+    expect(with10).toBe(Math.max(1, Math.floor(50 * 1 * 1.5))); // 75
+    expect(with10).toBeGreaterThan(base);
+  });
+
+  it("prestige bonus cappé à ×4 (80+ prestiges)", () => {
+    const at80 = computePrestigeDna(10e6, 80);
+    const at100 = computePrestigeDna(10e6, 100);
+    expect(at80).toBe(at100); // cap atteint
   });
 });
 
 // --- Arbre d'Évolution 3 voies ---
 
 describe("Evolution Tree (3 branches)", () => {
-  it("arbre a 18 nœuds répartis en 3 branches", () => {
+  it("arbre V2 : 3 branches + cross (~30 nœuds)", () => {
     const ponte = DEFAULT_EVOLUTION_TREE.filter((n) => n.branch === "ponte");
     const marais = DEFAULT_EVOLUTION_TREE.filter((n) => n.branch === "marais");
     const adaptation = DEFAULT_EVOLUTION_TREE.filter((n) => n.branch === "adaptation");
-    expect(ponte.length).toBe(6);
+    const cross = DEFAULT_EVOLUTION_TREE.filter((n) => n.branch === "cross");
-    expect(marais.length).toBe(6);
+    expect(ponte.length).toBe(8);
-    expect(adaptation.length).toBe(6);
+    expect(marais.length).toBe(8);
+    expect(adaptation.length).toBe(8);
+    expect(cross.length).toBe(1);
+    expect(DEFAULT_EVOLUTION_TREE.length).toBe(25);
   });
 
   describe("canBuyEvolutionNode", () => {
@@ -363,8 +383,8 @@ describe("Evolution Tree (3 branches)", () => {
           n.id === "ponte_frenetique" ? { ...n, unlocked: true } : n
         ),
       };
-      // auto_ponte exclusive_with ponte_frenetique → locked
+      // concentration exclusive_with ponte_frenetique → locked
-      expect(canBuyEvolutionNode(state, "auto_ponte")).toBe(false);
+      expect(canBuyEvolutionNode(state, "concentration")).toBe(false);
     });
 
     it("peut acheter un nœud exclusif si l'alternative n'est pas débloquée", () => {
@@ -375,7 +395,7 @@ describe("Evolution Tree (3 branches)", () => {
           n.id === "double_ponte" || n.id === "ponte_amelioree" ? { ...n, unlocked: true } : n
         ),
       };
-      expect(canBuyEvolutionNode(state, "auto_ponte")).toBe(true);
+      expect(canBuyEvolutionNode(state, "concentration")).toBe(true);
       expect(canBuyEvolutionNode(state, "ponte_frenetique")).toBe(true);
     });
   });
@@ -399,15 +419,17 @@ describe("Evolution Tree (3 branches)", () => {
       const state = {
         ...DEFAULT_STATE,
         ancestralDna: 50,
+        prestigeCount: 1,
+        freeResetAvailable: true,
         evolutionTree: DEFAULT_STATE.evolutionTree.map((n) =>
           n.id === "ponte_amelioree" || n.id === "instinct_gregaire"
             ? { ...n, unlocked: true }
             : n
         ),
       };
-      // ponte_amelioree (1) + instinct_gregaire (1) = 2 ADN spent
+      // ponte_amelioree (1) + instinct_gregaire (3) = 4 ADN spent, free reset
       const result = resetEvolutionTree(state);
-      expect(result.ancestralDna).toBe(52);
+      expect(result.ancestralDna).toBe(54);
       expect(result.evolutionTree.every((n) => !n.unlocked)).toBe(true);
     });
 
@@ -491,41 +513,27 @@ describe("Evolution Tree (3 branches)", () => {
     });
   });
 
-  describe("unlock_generator (Résilience)", () => {
+  describe("prestige reset generators", () => {
-    it("prestige avec Résilience donne 1 Lac Mystique", () => {
+    it("prestige remet les générateurs à 0", () => {
-      const state = {
-        ...DEFAULT_STATE,
-        resources: 2_000_000,
-        generators: DEFAULT_STATE.generators.map((g) => ({ ...g, owned: 5 })),
-        evolutionTree: DEFAULT_STATE.evolutionTree.map((n) =>
-          n.id === "resilience" ? { ...n, unlocked: true } : n
-        ),
-      };
-      const result = applyPrestige(state);
-      const lac = result.generators.find((g) => g.id === "lac");
-      expect(lac!.owned).toBe(1);
-    });
-
-    it("prestige sans Résilience donne 0 Lac Mystique", () => {
       const state = {
         ...DEFAULT_STATE,
         resources: 2_000_000,
+        lifetimeTadpoles: 2_000_000,
         generators: DEFAULT_STATE.generators.map((g) => ({ ...g, owned: 5 })),
       };
       const result = applyPrestige(state);
-      const lac = result.generators.find((g) => g.id === "lac");
+      expect(result.generators.every((g) => g.owned === 0)).toBe(true);
-      expect(lac!.owned).toBe(0);
     });
   });
 
   describe("auto_click (getAutoClicksPerSecond)", () => {
-    it("retourne 0 si auto_ponte non débloqué", () => {
+    it("retourne 0 si capstone ponte non débloqué", () => {
       expect(getAutoClicksPerSecond(DEFAULT_EVOLUTION_TREE)).toBe(0);
     });
 
-    it("retourne 1 si auto_ponte débloqué", () => {
+    it("retourne 1 si capstone Ponte Automatique débloqué", () => {
       const tree = DEFAULT_EVOLUTION_TREE.map((n) =>
-        n.id === "auto_ponte" ? { ...n, unlocked: true } : n
+        n.id === "ponte_auto" ? { ...n, unlocked: true } : n
       );
       expect(getAutoClicksPerSecond(tree)).toBe(1);
     });

Frontend/src/__tests__/migrateSave.test.ts

@@ -0,0 +1,123 @@
+import { describe, it, expect } from "vitest";
+import { migrateSave } from "../core/migrateSave";
+import { DEFAULT_EVOLUTION_TREE, DEFAULT_GENERATORS } from "../core/economy";
+import { CURRENT_SAVE_VERSION } from "../core/balance";
+
+// Minimal Sprint 2 save (v1 — no saveVersion field)
+function makeV1Save(overrides: Record<string, unknown> = {}) {
+  return {
+    resources: 1234,
+    clickMultiplier: 1,
+    generators: DEFAULT_GENERATORS.map((g) => ({ ...g, owned: 5 })),
+    lastTick: Date.now() - 60_000,
+    lastOnline: Date.now() - 60_000,
+    prestigeCount: 3,
+    prestigeMultiplier: 1.3,
+    ancestralDna: 42,
+    evolutionTree: DEFAULT_EVOLUTION_TREE.slice(0, 18).map((n, i) => ({
+      ...n,
+      unlocked: i < 2, // first 2 nodes unlocked
+    })),
+    lifetimeTadpoles: 5_000_000,
+    cosmeticInventory: ["hat_lily"],
+    cosmeticEquipped: { hat: "hat_lily" },
+    ...overrides,
+  };
+}
+
+describe("migrateSave", () => {
+  describe("v1 → v2", () => {
+    it("sets saveVersion to current", () => {
+      const result = migrateSave(makeV1Save());
+      expect(result.saveVersion).toBe(CURRENT_SAVE_VERSION);
+    });
+
+    it("adds runStats with defaults", () => {
+      const result = migrateSave(makeV1Save());
+      expect(result.runStats).toBeDefined();
+      expect(result.runStats.tadpolesProduced).toBe(0);
+      expect(result.runStats.bestRun).toBeNull();
+    });
+
+    it("adds freeResetAvailable and extraResetsUsed", () => {
+      const result = migrateSave(makeV1Save());
+      expect(result.freeResetAvailable).toBe(true);
+      expect(result.extraResetsUsed).toBe(0);
+    });
+
+    it("preserves unlocked state of existing tree nodes", () => {
+      const result = migrateSave(makeV1Save());
+      const node0 = result.evolutionTree.find((n) => n.id === "ponte_amelioree");
+      const node2 = result.evolutionTree.find((n) => n.id === "ponte_frenetique");
+      expect(node0?.unlocked).toBe(true);
+      expect(node2?.unlocked).toBe(false);
+    });
+
+    it("preserves generator owned counts", () => {
+      const result = migrateSave(makeV1Save());
+      expect(result.generators[0].owned).toBe(5);
+    });
+
+    it("preserves resources, ancestralDna, prestigeCount", () => {
+      const result = migrateSave(makeV1Save());
+      expect(result.resources).toBe(1234);
+      expect(result.ancestralDna).toBe(42);
+      expect(result.prestigeCount).toBe(3);
+    });
+
+    it("preserves cosmetics", () => {
+      const result = migrateSave(makeV1Save());
+      expect(result.cosmeticInventory).toContain("hat_lily");
+      expect(result.cosmeticEquipped.hat).toBe("hat_lily");
+    });
+  });
+
+  describe("backfill missing fields", () => {
+    it("backfills lastOnline from lastTick", () => {
+      const save = makeV1Save();
+      delete (save as Record<string, unknown>).lastOnline;
+      const result = migrateSave(save);
+      expect(result.lastOnline).toBe(save.lastTick);
+    });
+
+    it("backfills empty cosmeticInventory", () => {
+      const save = makeV1Save();
+      delete (save as Record<string, unknown>).cosmeticInventory;
+      const result = migrateSave(save);
+      expect(result.cosmeticInventory).toEqual([]);
+    });
+
+    it("backfills empty cosmeticEquipped", () => {
+      const save = makeV1Save();
+      delete (save as Record<string, unknown>).cosmeticEquipped;
+      const result = migrateSave(save);
+      expect(result.cosmeticEquipped).toEqual({});
+    });
+  });
+
+  describe("v2 passthrough", () => {
+    it("does not re-migrate a v2 save", () => {
+      const v2 = migrateSave(makeV1Save());
+      const result = migrateSave(v2 as unknown as Record<string, unknown>);
+      expect(result.saveVersion).toBe(CURRENT_SAVE_VERSION);
+      expect(result).toEqual(v2);
+    });
+  });
+
+  describe("edge cases", () => {
+    it("handles save with no evolutionTree (corrupted)", () => {
+      const save = makeV1Save();
+      delete (save as Record<string, unknown>).evolutionTree;
+      const result = migrateSave(save);
+      expect(result.evolutionTree.length).toBe(DEFAULT_EVOLUTION_TREE.length);
+    });
+
+    it("handles save with no generators (corrupted)", () => {
+      const save = makeV1Save();
+      delete (save as Record<string, unknown>).generators;
+      const result = migrateSave(save);
+      expect(result.generators.length).toBe(DEFAULT_GENERATORS.length);
+      expect(result.generators[0].owned).toBe(0);
+    });
+  });
+});

Frontend/src/__tests__/milestones.test.ts

@@ -0,0 +1,101 @@
+import { describe, it, expect } from "vitest";
+import {
+  DEFAULT_STATE,
+  getClaimableMilestones,
+  getNextMilestone,
+  claimMilestone,
+  getMilestoneStartNid,
+  getMilestoneOfflineBonus,
+} from "../core/economy";
+
+describe("Prestige Milestones", () => {
+  it("no claimable milestones at 0 prestiges", () => {
+    expect(getClaimableMilestones(DEFAULT_STATE)).toEqual([]);
+  });
+
+  it("milestone_1 claimable at 1 prestige", () => {
+    const state = { ...DEFAULT_STATE, prestigeCount: 1 };
+    const claimable = getClaimableMilestones(state);
+    expect(claimable.length).toBe(1);
+    expect(claimable[0].id).toBe("milestone_1");
+  });
+
+  it("multiple milestones claimable at 5 prestiges", () => {
+    const state = { ...DEFAULT_STATE, prestigeCount: 5 };
+    const claimable = getClaimableMilestones(state);
+    expect(claimable.length).toBe(3); // 1, 3, 5
+  });
+
+  it("already claimed milestones not returned", () => {
+    const state = {
+      ...DEFAULT_STATE,
+      prestigeCount: 5,
+      claimedMilestones: ["milestone_1", "milestone_3"],
+    };
+    const claimable = getClaimableMilestones(state);
+    expect(claimable.length).toBe(1);
+    expect(claimable[0].id).toBe("milestone_5");
+  });
+
+  it("getNextMilestone returns first unachieved", () => {
+    const state = { ...DEFAULT_STATE, prestigeCount: 2 };
+    const next = getNextMilestone(state);
+    expect(next?.id).toBe("milestone_3");
+    expect(next?.threshold).toBe(3);
+  });
+
+  it("getNextMilestone returns null when all achieved", () => {
+    const state = { ...DEFAULT_STATE, prestigeCount: 200 };
+    expect(getNextMilestone(state)).toBeNull();
+  });
+
+  describe("claimMilestone", () => {
+    it("claims successfully and adds to claimedMilestones", () => {
+      const state = { ...DEFAULT_STATE, prestigeCount: 1 };
+      const result = claimMilestone(state, "milestone_1");
+      expect(result).not.toBeNull();
+      expect(result!.claimedMilestones).toContain("milestone_1");
+    });
+
+    it("cosmetic reward adds to inventory", () => {
+      const state = { ...DEFAULT_STATE, prestigeCount: 1 };
+      const result = claimMilestone(state, "milestone_1");
+      expect(result!.cosmeticInventory).toContain("ribbon");
+    });
+
+    it("cannot claim milestone not yet reached", () => {
+      const result = claimMilestone(DEFAULT_STATE, "milestone_1");
+      expect(result).toBeNull();
+    });
+
+    it("cannot claim already claimed milestone", () => {
+      const state = {
+        ...DEFAULT_STATE,
+        prestigeCount: 1,
+        claimedMilestones: ["milestone_1"],
+      };
+      const result = claimMilestone(state, "milestone_1");
+      expect(result).toBeNull();
+    });
+  });
+
+  describe("milestone bonuses", () => {
+    it("getMilestoneStartNid returns 0 without milestone_5", () => {
+      expect(getMilestoneStartNid(DEFAULT_STATE)).toBe(0);
+    });
+
+    it("getMilestoneStartNid returns 1 with milestone_5 claimed", () => {
+      const state = { ...DEFAULT_STATE, claimedMilestones: ["milestone_5"] };
+      expect(getMilestoneStartNid(state)).toBe(1);
+    });
+
+    it("getMilestoneOfflineBonus returns 0 without milestone_15", () => {
+      expect(getMilestoneOfflineBonus(DEFAULT_STATE)).toBe(0);
+    });
+
+    it("getMilestoneOfflineBonus returns 0.05 with milestone_15 claimed", () => {
+      const state = { ...DEFAULT_STATE, claimedMilestones: ["milestone_15"] };
+      expect(getMilestoneOfflineBonus(state)).toBe(0.05);
+    });
+  });
+});

Frontend/src/components/EvolutionTree.tsx

@@ -1,28 +1,43 @@
-// EvolutionTree.tsx — Arbre d'Évolution 3 voies (permanent — jamais reset par prestige)
+// EvolutionTree.tsx — Arbre d'Évolution V2 (Sprint 3)
+// 3 branches + capstones + post-capstone repeatables + Convergence évolutif
 
 import { useGameStore } from "../store/useGameStore";
-import { canBuyEvolutionNode, getSpentDna } from "../core/economy";
+import {
+  canBuyEvolutionNode,
+  getSpentDna,
+  getTreeResetCost,
+  canResetTree,
+  getRepeatableCost,
+  canUpgradeConvergence,
+} from "../core/economy";
 import type { EvolutionNode, Branch } from "../core/economy";
+import { formatNumber } from "../utils/formatNumber";
 
-const EFFECT_LABELS: Record<string, (v: number) => string> = {
+const EFFECT_LABELS: Record<string, (v: number, n?: EvolutionNode) => string> = {
   click_multiplier: (v) => `x${v} ponte`,
   production_multiplier: (v) => `x${v} production`,
-  start_bonus: (v) => `+${v} têtards au départ`,
+  start_bonus: (v) => `+${v} tetards au depart`,
-  unlock_generator: () => `Lac Mystique dès le début`,
+  unlock_generator: () => `Lac Mystique des le debut`,
   double_click_chance: (v) => `${(v * 100).toFixed(0)}% chance double ponte`,
-  auto_click: (v) => `${v} auto-ponte/s`,
+  auto_click: (v, n) => n?.repeatable ? `+${(v * 100).toFixed(0)}%/achat` : `${v} auto-ponte/s`,
+  auto_click_scaling: (v) => `${v} auto-ponte/s (scale)`,
   crit_click_chance: (v) => `${(v * 100).toFixed(0)}% chance crit x10`,
   generator_boost: (v) => `x${v} Nid`,
-  cost_reduction: (v) => `-${(v * 100).toFixed(0)}% coût générateurs`,
+  generator_synergy: (v, n) => n?.repeatable ? `+${(v * 100).toFixed(0)}%/achat` : `+${(v * 100).toFixed(0)}% par type`,
+  cost_reduction: (v) => `-${(v * 100).toFixed(0)}% cout generateurs`,
   prestige_dna_bonus: (v) => `+${(v * 100).toFixed(0)}% ADN prestige`,
-  offline_boost: (v) => `+${(v * 100).toFixed(0)}% gains offline`,
+  offline_boost: (v, n) => n?.repeatable ? `+${(v * 100).toFixed(0)}%/achat` : `+${(v * 100).toFixed(0)}% gains offline`,
-  prestige_threshold_reduction: (v) => `Prestige à ${((1 - v) * 100).toFixed(0)}% du seuil`,
+  offline_cap_boost: (v) => `Offline cap → ${(v * 100).toFixed(0)}%, duree 8h`,
+  prestige_threshold_reduction: (v) => `Prestige a ${((1 - v) * 100).toFixed(0)}% du seuil`,
+  all_effects_boost: (v) => `+${(v * 100).toFixed(0)}% tous effets`,
+  post_capstone_discount: (v) => `-${(v * 100).toFixed(0)}% cout post-capstones`,
 };
 
-const BRANCH_CONFIG: Record<Branch, { label: string; color: string; accent: string }> = {
+const BRANCH_CONFIG: Record<Branch | "cross", { label: string; color: string; accent: string }> = {
   ponte:      { label: "Ponte",        color: "border-emerald-500/30", accent: "gp-accent-green" },
   marais:     { label: "Marais",       color: "border-blue-500/30",    accent: "text-blue-400" },
   adaptation: { label: "Adaptation",   color: "border-amber-500/30",   accent: "gp-accent-amber" },
+  cross:      { label: "Convergence",  color: "border-purple-500/30",  accent: "gp-accent-purple" },
 };
 
 function NodeRow({
@@ -36,36 +51,62 @@ function NodeRow({
   isExcluded: boolean;
   onBuy: () => void;
 }) {
+  const isCapstone = node.capstone;
+  const isRepeatable = node.repeatable;
+  const purchased = node.purchased ?? 0;
+
   const rowClass = node.unlocked
-    ? "gp-row gp-row--unlocked"
+    ? isCapstone
+      ? "gp-row gp-row--unlocked border-amber-400/40!"
+      : "gp-row gp-row--unlocked"
     : isExcluded
     ? "gp-row gp-row--locked opacity-30!"
     : canBuy
-    ? "gp-row gp-row--evolution"
+    ? isCapstone
+      ? "gp-row gp-row--evolution border-amber-400/30!"
+      : "gp-row gp-row--evolution"
     : "gp-row gp-row--locked";
 
+  const cost = isRepeatable && node.unlocked
+    ? getRepeatableCost(node)
+    : isRepeatable
+    ? node.cost
+    : node.cost;
+
   return (
     <div className={rowClass}>
       <div className="flex flex-col min-w-0">
         <div className="flex items-center gap-1">
+          {isCapstone && <span className="text-amber-400 text-[0.6rem]">★</span>}
           <span className="gp-value text-[0.7rem]!">{node.name}</span>
+          {isRepeatable && node.unlocked && (
+            <span className="gp-label text-[0.55rem]!">x{purchased}</span>
+          )}
           {node.exclusive_with && !node.unlocked && !isExcluded && (
             <span className="gp-label text-[0.55rem]!">OU</span>
           )}
         </div>
-        <span className="gp-label">{EFFECT_LABELS[node.effect]?.(node.value) ?? node.effect}</span>
+        <span className="gp-label">{EFFECT_LABELS[node.effect]?.(node.value, node) ?? node.effect}</span>
       </div>
-      {node.unlocked ? (
+      {node.unlocked && !isRepeatable ? (
         <span className="gp-label gp-accent-green">OK</span>
+      ) : node.unlocked && isRepeatable ? (
+        <button
+          disabled={!canBuy}
+          onClick={onBuy}
+          className={`gp-btn ${canBuy ? "gp-btn--buy" : "gp-btn--disabled"}`}
+        >
+          {formatNumber(cost)}
+        </button>
       ) : isExcluded ? (
-        <span className="gp-label text-[0.55rem]!">verrouillé</span>
+        <span className="gp-label text-[0.55rem]!">verrouille</span>
       ) : (
         <button
           disabled={!canBuy}
           onClick={onBuy}
           className={`gp-btn ${canBuy ? "gp-btn--buy" : "gp-btn--disabled"}`}
         >
-          {node.cost}
+          {formatNumber(cost)}
         </button>
       )}
     </div>
@@ -99,6 +140,74 @@ function BranchColumn({ branch }: { branch: Branch }) {
   );
 }
 
+function ConvergenceSection() {
+  const state = useGameStore((s) => s.state);
+  const buyNode = useGameStore((s) => s.buyNode);
+  const upgradeConv = useGameStore((s) => s.upgradeConvergenceNode);
+  const conv = state.evolutionTree.find((n) => n.id === "convergence");
+
+  if (!conv) return null;
+
+  const canBuy = canBuyEvolutionNode(state, "convergence");
+  const canUpgrade = canUpgradeConvergence(state);
+  const tier = conv.tier ?? 1;
+  const maxTier = conv.maxTier ?? 2;
+  const tierName = tier >= 2 ? "Omega" : "Alpha";
+
+  return (
+    <div className="gp border-t-2 border-purple-500/30">
+      <span className="gp-title text-center gp-accent-purple">
+        Convergence {conv.unlocked ? tierName : ""}
+      </span>
+      {conv.unlocked ? (
+        <div className="flex flex-col gap-1">
+          <div className="gp-row gp-row--unlocked border-purple-400/30!">
+            <div className="flex flex-col">
+              <span className="gp-value text-[0.7rem]!">
+                {tier >= 2 ? "Omega" : "Alpha"} (tier {tier}/{maxTier})
+              </span>
+              <span className="gp-label">
+                {tier >= 2
+                  ? "+10% tous effets + -20% cout post-capstones"
+                  : "+10% a tous les effets de l'arbre"
+                }
+              </span>
+            </div>
+            <span className="gp-label gp-accent-green">OK</span>
+          </div>
+          {tier < maxTier && (
+            <button
+              disabled={!canUpgrade}
+              onClick={upgradeConv}
+              className={`gp-btn ${canUpgrade ? "gp-btn--buy" : "gp-btn--disabled"} w-full`}
+            >
+              {canUpgrade
+                ? `Evoluer → Omega (${conv.tierUpgradeCost} ADN)`
+                : `Requis : 2 capstones (${conv.tierUpgradeCost} ADN)`
+              }
+            </button>
+          )}
+        </div>
+      ) : (
+        <div className="gp-row gp-row--locked">
+          <div className="flex flex-col">
+            <span className="gp-value text-[0.7rem]!">Convergence Alpha</span>
+            <span className="gp-label">+10% a tous les effets de l'arbre</span>
+            <span className="gp-label text-[0.55rem]!">Requis : 1 capstone + tier 3 d'une 2e branche</span>
+          </div>
+          <button
+            disabled={!canBuy}
+            onClick={() => buyNode("convergence")}
+            className={`gp-btn ${canBuy ? "gp-btn--buy" : "gp-btn--disabled"}`}
+          >
+            {conv.cost}
+          </button>
+        </div>
+      )}
+    </div>
+  );
+}
+
 export function EvolutionTree() {
   const state = useGameStore((s) => s.state);
   const resetTree = useGameStore((s) => s.resetTree);
@@ -108,13 +217,16 @@ export function EvolutionTree() {
 
   const spentDna = getSpentDna(evolutionTree);
   const hasUnlocked = spentDna > 0;
+  const resetCost = getTreeResetCost(state);
+  const canReset = canResetTree(state);
 
   const handleReset = () => {
-    if (!hasUnlocked) return;
+    if (!canReset) return;
+    const costLabel = resetCost > 0 ? ` (coute ${resetCost} ADN)` : " (gratuit)";
     const confirmed = window.confirm(
-      `Réinitialiser l'Arbre d'Évolution ?\n\n` +
+      `Reinitialiser l'Arbre d'Evolution ?\n\n` +
-      `Tu récupères ${spentDna} ADN Ancestral.\n` +
+      `Tu recuperes ${spentDna} ADN Ancestral.${costLabel}\n` +
-      `Tous les nœuds seront verrouillés.\n\n` +
+      `Tous les noeuds seront verrouilles.\n\n` +
       `Confirmer ?`
     );
     if (confirmed) resetTree();
@@ -123,16 +235,21 @@ export function EvolutionTree() {
   return (
     <div className="flex flex-col gap-2">
       <div className="flex justify-between items-center px-1">
-        <span className="gp-title">Évolution</span>
+        <span className="gp-title">Evolution</span>
         <div className="flex items-center gap-2">
-          <span className="gp-value gp-accent-amber">{ancestralDna} ADN</span>
+          <span className="gp-value gp-accent-amber">{formatNumber(ancestralDna)} ADN</span>
           {hasUnlocked && (
             <button
               onClick={handleReset}
-              className="gp-btn gp-btn--disabled text-[0.55rem]! hover:bg-red-500/20! hover:text-red-400!"
+              disabled={!canReset}
-              title={`Récupérer ${spentDna} ADN`}
+              className={`gp-btn text-[0.55rem]! ${
+                canReset
+                  ? "gp-btn--disabled hover:bg-red-500/20! hover:text-red-400!"
+                  : "gp-btn--disabled"
+              }`}
+              title={`Recuperer ${spentDna} ADN${resetCost > 0 ? ` (coute ${resetCost})` : " (gratuit)"}`}
             >
-              Reset
+              Reset{resetCost > 0 ? ` (${resetCost})` : ""}
             </button>
           )}
         </div>
@@ -142,6 +259,7 @@ export function EvolutionTree() {
         <BranchColumn branch="marais" />
         <BranchColumn branch="adaptation" />
       </div>
+      <ConvergenceSection />
     </div>
   );
 }

Frontend/src/components/MilestonesPanel.tsx

@@ -0,0 +1,89 @@
+// MilestonesPanel.tsx — Paliers de prestige (Sprint 3)
+// Progress bar vers le prochain milestone, claim button, preview reward
+
+import { useGameStore } from "../store/useGameStore";
+import { getClaimableMilestones, getNextMilestone } from "../core/economy";
+import { PRESTIGE_MILESTONES } from "../data/prestigeMilestones";
+
+export function MilestonesPanel() {
+  const state = useGameStore((s) => s.state);
+  const claim = useGameStore((s) => s.claimMilestone);
+
+  if (state.prestigeCount < 1) return null;
+
+  const claimable = getClaimableMilestones(state);
+  const nextMilestone = getNextMilestone(state);
+  const totalClaimed = state.claimedMilestones.length;
+
+  return (
+    <div className="gp">
+      <div className="flex justify-between items-center">
+        <span className="gp-title">Milestones</span>
+        <span className="gp-label">{totalClaimed}/{PRESTIGE_MILESTONES.length}</span>
+      </div>
+
+      {/* Claimable milestones */}
+      {claimable.length > 0 && (
+        <div className="flex flex-col gap-1.5">
+          {claimable.map((m) => (
+            <div key={m.id} className="gp-row gp-row--evolution border-purple-400/30!">
+              <div className="flex flex-col min-w-0">
+                <span className="gp-value text-[0.7rem]!">{m.name}</span>
+                <span className="gp-label">{m.reward.label}</span>
+              </div>
+              <button
+                onClick={() => claim(m.id)}
+                className="gp-btn gp-btn--buy"
+              >
+                Claim
+              </button>
+            </div>
+          ))}
+        </div>
+      )}
+
+      {/* Progress vers le prochain milestone */}
+      {nextMilestone && (
+        <div className="flex flex-col gap-1">
+          <div className="flex justify-between">
+            <span className="gp-label">Prochain : {nextMilestone.name}</span>
+            <span className="gp-label">
+              {state.prestigeCount}/{nextMilestone.threshold}
+            </span>
+          </div>
+          <div className="gp-progress">
+            <div
+              className="gp-progress-fill bg-gradient-to-r from-purple-600 to-purple-400"
+              style={{
+                width: `${Math.min((state.prestigeCount / nextMilestone.threshold) * 100, 100).toFixed(1)}%`,
+              }}
+            />
+          </div>
+          <span className="gp-label">{nextMilestone.reward.label}</span>
+        </div>
+      )}
+
+      {/* Tous les milestones réclamés */}
+      {!nextMilestone && claimable.length === 0 && (
+        <span className="gp-label text-center gp-accent-purple">
+          Tous les milestones reclames !
+        </span>
+      )}
+
+      {/* Liste compacte des milestones passés */}
+      {totalClaimed > 0 && claimable.length === 0 && (
+        <div className="flex flex-wrap gap-1 mt-1">
+          {PRESTIGE_MILESTONES.filter((m) => state.claimedMilestones.includes(m.id)).map((m) => (
+            <span
+              key={m.id}
+              className="gp-label text-[0.55rem]! px-1.5 py-0.5 rounded bg-purple-500/10 border border-purple-500/20"
+              title={`${m.name} — ${m.description}`}
+            >
+              {m.threshold}
+            </span>
+          ))}
+        </div>
+      )}
+    </div>
+  );
+}

Frontend/src/components/PrestigePanel.tsx

@@ -5,28 +5,15 @@ import { computePrestigeDna, getPrestigeDnaBonus, getPrestigeThreshold } from ".
 import { formatNumber } from "../utils/formatNumber";
 
 export function PrestigePanel() {
-  const { lifetimeTadpoles } = useGameStore((s) => s.state);
-  const canPrestige = useGameStore((s) => s.canPrestige);
-  const prestige = useGameStore((s) => s.prestige);
-
   const state = useGameStore((s) => s.state);
-  const baseDna = computePrestigeDna(lifetimeTadpoles);
+  const canPrestige = useGameStore((s) => s.canPrestige);
+  const openPrestigeScreen = useGameStore((s) => s.openPrestigeScreen);
+
+  const baseDna = computePrestigeDna(state.lifetimeTadpoles, state.prestigeCount);
   const dnaBonus = getPrestigeDnaBonus(state.evolutionTree);
   const dnaPreview = Math.floor(baseDna * (1 + dnaBonus));
   const threshold = getPrestigeThreshold(state);
 
-  const handlePrestige = () => {
-    const confirmed = window.confirm(
-      `Nouvelle Génération\n\n` +
-        `Reset : têtards et générateurs à zéro.\n` +
-        `Récompense : +${dnaPreview} ADN Ancestral\n` +
-        `              +0.1x multiplicateur permanent\n\n` +
-        `L'Arbre d'Évolution persiste.\n\n` +
-        `Confirmer ?`
-    );
-    if (confirmed) prestige();
-  };
-
   return (
     <div className="gp">
       <span className="gp-title" title="Recommence à zéro en échange d'un bonus permanent — tes têtards et générateurs sont réinitialisés mais tu gagnes de l'ADN et un multiplicateur">Prestige</span>
@@ -35,12 +22,12 @@ export function PrestigePanel() {
           <span className="gp-value gp-accent-purple">
             +{dnaPreview} ADN · +0.1x mult
           </span>
-          <button onClick={handlePrestige} className="gp-btn gp-btn--prestige">
+          <button onClick={openPrestigeScreen} className="gp-btn gp-btn--prestige">
-            Nouvelle Génération
+            Nouvelle Generation
           </button>
         </div>
       ) : (
-        <span className="gp-label">Atteins {formatNumber(threshold)} têtards pour prestige</span>
+        <span className="gp-label">Atteins {formatNumber(threshold)} tetards pour prestige</span>
       )}
     </div>
   );

Frontend/src/components/PrestigeScreen.tsx

@@ -0,0 +1,182 @@
+// PrestigeScreen.tsx — Écran de prestige fullscreen (Sprint 3)
+// Preview ADN, stats de run, comparaison meilleure run, confirmation
+
+import { useGameStore } from "../store/useGameStore";
+import {
+  computePrestigeDna,
+  getPrestigeDnaBonus,
+  getPrestigeThreshold,
+} from "../core/economy";
+import { formatNumber } from "../utils/formatNumber";
+
+function formatDuration(ms: number): string {
+  const totalSeconds = Math.floor(ms / 1000);
+  const hours = Math.floor(totalSeconds / 3600);
+  const minutes = Math.floor((totalSeconds % 3600) / 60);
+  const seconds = totalSeconds % 60;
+  if (hours > 0) return `${hours}h ${minutes}m`;
+  if (minutes > 0) return `${minutes}m ${seconds}s`;
+  return `${seconds}s`;
+}
+
+export function PrestigeScreen() {
+  const show = useGameStore((s) => s.showPrestigeScreen);
+  const close = useGameStore((s) => s.closePrestigeScreen);
+  const prestige = useGameStore((s) => s.prestige);
+  const state = useGameStore((s) => s.state);
+
+  if (!show) return null;
+
+  const baseDna = computePrestigeDna(state.lifetimeTadpoles, state.prestigeCount);
+  const dnaBonus = getPrestigeDnaBonus(state.evolutionTree);
+  const dnaPreview = Math.floor(baseDna * (1 + dnaBonus));
+  const threshold = getPrestigeThreshold(state);
+  const canPrestige = state.lifetimeTadpoles >= threshold;
+
+  // Run stats
+  const now = Date.now();
+  const runDuration = now - state.runStats.startedAt;
+  const bestRun = state.runStats.bestRun;
+
+  // Comparison with best run
+  const isBestAdn = !bestRun || dnaPreview > bestRun.adn;
+  const isBestTadpoles = !bestRun || state.lifetimeTadpoles > bestRun.tadpoles;
+
+  const handlePrestige = () => {
+    if (canPrestige) prestige();
+  };
+
+  return (
+    <div className="fixed inset-0 z-50 flex items-center justify-center bg-black/85 backdrop-blur-sm">
+      <div className="gp max-w-md w-full mx-4">
+        {/* Header */}
+        <div className="text-center">
+          <span className="gp-title text-lg!">Nouvelle Generation</span>
+          <p className="gp-label mt-1">
+            Generation #{state.prestigeCount + 1}
+          </p>
+        </div>
+
+        <div className="gp-sep" />
+
+        {/* ADN Preview */}
+        <div className="flex flex-col items-center gap-1 py-2">
+          <span className="gp-label">ADN Ancestral</span>
+          <span className="text-3xl font-extrabold" style={{ color: "#a78bfa", fontFamily: "var(--font)" }}>
+            +{formatNumber(dnaPreview)}
+          </span>
+          {dnaBonus > 0 && (
+            <span className="gp-label">
+              (base {formatNumber(baseDna)} + {Math.round(dnaBonus * 100)}% arbre)
+            </span>
+          )}
+          <span className="gp-label mt-1">
+            Total apres : {formatNumber(state.ancestralDna + dnaPreview)} ADN
+          </span>
+        </div>
+
+        <div className="gp-sep" />
+
+        {/* Run Stats */}
+        <div className="flex flex-col gap-2">
+          <span className="gp-zone-label">Stats de la run</span>
+
+          <div className="flex justify-between">
+            <span className="gp-label">Duree</span>
+            <span className="gp-value">{formatDuration(runDuration)}</span>
+          </div>
+
+          <div className="flex justify-between">
+            <span className="gp-label">Tetards produits</span>
+            <span className={`gp-value ${isBestTadpoles ? "gp-accent-green" : ""}`}>
+              {formatNumber(state.lifetimeTadpoles)}
+              {isBestTadpoles && bestRun && " ★"}
+            </span>
+          </div>
+
+          <div className="flex justify-between">
+            <span className="gp-label">ADN cette run</span>
+            <span className={`gp-value ${isBestAdn ? "gp-accent-green" : ""}`}>
+              {formatNumber(dnaPreview)}
+              {isBestAdn && bestRun && " ★"}
+            </span>
+          </div>
+
+          {bestRun && (
+            <div className="flex justify-between">
+              <span className="gp-label">Vitesse vs meilleure</span>
+              <span className={`gp-value ${
+                runDuration < bestRun.duration ? "gp-accent-green" : "gp-accent-amber"
+              }`}>
+                {runDuration < bestRun.duration
+                  ? `${Math.round((1 - runDuration / bestRun.duration) * 100)}% plus rapide`
+                  : runDuration > bestRun.duration
+                    ? `${Math.round((runDuration / bestRun.duration - 1) * 100)}% plus lent`
+                    : "identique"
+                }
+              </span>
+            </div>
+          )}
+        </div>
+
+        {bestRun && (
+          <>
+            <div className="gp-sep" />
+            <div className="flex flex-col gap-1">
+              <span className="gp-zone-label">Meilleure run</span>
+              <div className="flex justify-between">
+                <span className="gp-label">Duree</span>
+                <span className="gp-value">{formatDuration(bestRun.duration)}</span>
+              </div>
+              <div className="flex justify-between">
+                <span className="gp-label">ADN</span>
+                <span className="gp-value gp-accent-purple">{formatNumber(bestRun.adn)}</span>
+              </div>
+            </div>
+          </>
+        )}
+
+        <div className="gp-sep" />
+
+        {/* Reset info */}
+        <div className="text-center">
+          <p className="gp-label">
+            Tetards et generateurs remis a zero.
+          </p>
+          <p className="gp-label">
+            Arbre d'Evolution et cosmetiques conserves.
+          </p>
+          <p className="gp-label mt-1">
+            +1 reset d'arbre gratuit offert.
+          </p>
+        </div>
+
+        {/* Actions */}
+        <div className="flex gap-2 mt-1">
+          <button
+            onClick={close}
+            className="gp-btn flex-1 py-2!"
+            style={{ background: "rgba(255,255,255,0.08)", color: "rgba(255,255,255,0.7)" }}
+          >
+            Annuler
+          </button>
+          {canPrestige ? (
+            <button
+              onClick={handlePrestige}
+              className="gp-btn gp-btn--prestige flex-1 py-2!"
+            >
+              Nouvelle Generation
+            </button>
+          ) : (
+            <button
+              className="gp-btn gp-btn--disabled flex-1 py-2!"
+              disabled
+            >
+              {formatNumber(threshold - state.lifetimeTadpoles)} tetards manquants
+            </button>
+          )}
+        </div>
+      </div>
+    </div>
+  );
+}

Frontend/src/core/balance.ts

@@ -0,0 +1,68 @@
+// balance.ts — Constantes d'équilibrage centralisées
+// Toutes les valeurs de tuning en un seul fichier pour faciliter le playtest.
+// Sprint 3 — session brainstorm 2026-03-28
+
+// --- Formule ADN prestige ---
+
+export const PRESTIGE_ADN_BASE = 50;
+export const PRESTIGE_ADN_THRESHOLD = 1e6; // 1M têtards minimum pour prestige
+export const PRESTIGE_BONUS_PER_PRESTIGE = 0.05; // +5% par prestige
+export const PRESTIGE_BONUS_CAP = 3.0; // cap à ×4 total (80 prestiges)
+export const PRESTIGE_ADN_MIN = 1; // clamp : jamais 0 ADN si seuil atteint
+
+// --- Seuil prestige ---
+
+export const BASE_PRESTIGE_THRESHOLD = 1_000_000; // 1M têtards
+
+// --- Post-capstone scaling par tranche ---
+
+export const POST_CAPSTONE_TIERS = [
+  { maxPurchases: 5, multiplier: 1.5 },  // achats 1-5
+  { maxPurchases: 10, multiplier: 1.8 }, // achats 6-10
+  { maxPurchases: Infinity, multiplier: 2.0 }, // achats 11+
+] as const;
+
+/**
+ * Calcule le coût du N-ième achat post-capstone repeatable (0-indexed).
+ * Scaling par tranche : ×1.5 (achats 0-4), ×1.8 (5-9), ×2.0 (10+)
+ */
+export function postCapstoneCost(baseCost: number, purchased: number): number {
+  let cost = baseCost;
+  for (let i = 0; i < purchased; i++) {
+    if (i < 5) cost *= 1.5;
+    else if (i < 10) cost *= 1.8;
+    else cost *= 2.0;
+  }
+  return Math.floor(cost);
+}
+
+// --- Reset arbre ---
+
+export const TREE_RESET_FREE_PER_PRESTIGE = 1; // 1 gratuit par prestige
+export const TREE_RESET_EXTRA_COST = 5; // 5 ADN × n pour les resets supplémentaires
+
+/**
+ * Coût du prochain reset arbre.
+ * 1 gratuit par prestige, puis linéaire (5 × n) au-delà.
+ */
+export function treeResetCost(freeResetAvailable: boolean, extraResetsUsed: number): number {
+  if (freeResetAvailable) return 0;
+  return TREE_RESET_EXTRA_COST * (extraResetsUsed + 1);
+}
+
+// --- Offline ---
+
+export const OFFLINE_THRESHOLD_MS = 60_000; // 60s
+export const OFFLINE_FULL_MS = 15 * 60_000; // 0-15min : 100%
+export const OFFLINE_DECAY_END_MS = 60 * 60_000; // 15min-1h : 100% → 25%
+export const OFFLINE_ZERO_MS = 2 * 60 * 60_000; // 1h-2h : 25% → 0%
+export const OFFLINE_FLOOR = 0.25; // plancher decay
+
+// --- Anti-cheat ---
+
+export const MAX_PRODUCTION_PER_SECOND = 750_000;
+export const CHEAT_MARGIN = 1.1;
+
+// --- Save version ---
+
+export const CURRENT_SAVE_VERSION = 2;

Frontend/src/core/economy.ts

@@ -1,6 +1,25 @@
 // economy.ts — Core clicker logic (lazy calculation pattern)
 // Jamais de timer actif : tout est calculé au read depuis lastTick
 
+import {
+  PRESTIGE_ADN_BASE,
+  PRESTIGE_ADN_THRESHOLD,
+  PRESTIGE_BONUS_PER_PRESTIGE,
+  PRESTIGE_BONUS_CAP,
+  PRESTIGE_ADN_MIN,
+  BASE_PRESTIGE_THRESHOLD,
+  OFFLINE_THRESHOLD_MS as OFFLINE_THRESHOLD,
+  OFFLINE_FULL_MS,
+  OFFLINE_DECAY_END_MS,
+  OFFLINE_ZERO_MS,
+  OFFLINE_FLOOR,
+  CURRENT_SAVE_VERSION,
+  treeResetCost,
+  postCapstoneCost,
+} from "./balance";
+import { PRESTIGE_MILESTONES } from "../data/prestigeMilestones";
+import type { PrestigeMilestone } from "../data/prestigeMilestones";
+
 export interface Generator {
   id: string;
   name: string;
@@ -21,27 +40,54 @@ export type EffectType =
   | "cost_reduction"
   | "prestige_dna_bonus"
   | "offline_boost"
-  | "prestige_threshold_reduction";
+  | "prestige_threshold_reduction"
+  // Sprint 3 — capstones
+  | "auto_click_scaling"     // Ponte Auto — auto-click scale avec upgrades
+  | "generator_synergy"      // Symbiose Totale — +X% par type possédé
+  | "offline_cap_boost"      // Mémoire du Marais — offline cap + durée
+  // Sprint 3 — Convergence
+  | "all_effects_boost"      // +X% à tous les effets
+  | "post_capstone_discount"; // -X% coût post-capstones
 
-export type Branch = "ponte" | "marais" | "adaptation";
+export type Branch = "ponte" | "marais" | "adaptation" | "cross";
 
 export interface EvolutionNode {
   id: string;
   name: string;
-  cost: number;           // en ADN Ancestral
+  cost: number;           // en ADN Ancestral (base cost for repeatables)
   effect: EffectType;
   value: number;
   unlocked: boolean;
   requires: string | null;      // id du nœud prérequis (null = racine)
   branch: Branch;
   exclusive_with?: string;      // id du nœud alternatif (pick one)
+  // Sprint 3 — capstone & repeatable
+  capstone?: boolean;           // nœud capstone (bordure dorée, game-changer)
+  repeatable?: boolean;         // post-capstone achetable en boucle
+  purchased?: number;           // nombre d'achats pour les repeatables
+  // Sprint 3 — Convergence (nœud évolutif)
+  tier?: number;                // tier actuel (1 = Alpha, 2 = Omega)
+  maxTier?: number;             // tier max
+  tierUpgradeCost?: number;     // coût upgrade au tier suivant
+  tierUpgradeRequires?: string; // condition pour upgrade ("2_capstones")
 }
 
 export interface CosmeticSlotMap {
   [slot: string]: string | undefined;
 }
 
+export interface RunStats {
+  startedAt: number;          // timestamp ms début de la run
+  tadpolesProduced: number;   // têtards produits cette run (tracking granulaire)
+  bestRun: {
+    duration: number;         // ms
+    tadpoles: number;
+    adn: number;
+  } | null;
+}
+
 export interface GameState {
+  saveVersion: number;
   resources: number;
   clickMultiplier: number;
   generators: Generator[];
@@ -54,46 +100,214 @@ export interface GameState {
   lifetimeTadpoles: number; // total cumulé de la run (pour calcul ADN)
   cosmeticInventory: string[];       // ids des cosmétiques débloqués
   cosmeticEquipped: CosmeticSlotMap; // slot → cosmetic id
+  // Sprint 3
+  runStats: RunStats;
+  freeResetAvailable: boolean;  // 1 gratuit par prestige
+  extraResetsUsed: number;      // resets payants dans la génération courante
+  claimedMilestones: string[];  // IDs des milestones réclamés
 }
 
 // --- Arbre d'Évolution ---
 
 export const DEFAULT_EVOLUTION_TREE: EvolutionNode[] = [
-  // --- Ponte (click) ---
+  // ═══ PONTE (click) — 10 nœuds ═══
+
+  // Tier 1
   { id: "ponte_amelioree",  name: "Ponte Améliorée",     cost: 1,   effect: "click_multiplier",    value: 2,    unlocked: false, requires: null,                branch: "ponte" },
-  { id: "double_ponte",     name: "Double Ponte",     cost: 3,  effect: "double_click_chance", value: 0.10, unlocked: false, requires: "ponte_amelioree",  branch: "ponte" },
+  // Tier 2
-  { id: "ponte_frenetique", name: "Ponte Frénétique", cost: 8,  effect: "click_multiplier",    value: 3,    unlocked: false, requires: "double_ponte",     branch: "ponte", exclusive_with: "auto_ponte" },
+  { id: "double_ponte",     name: "Double Ponte",        cost: 5,   effect: "double_click_chance", value: 0.10, unlocked: false, requires: "ponte_amelioree",  branch: "ponte" },
-  { id: "auto_ponte",       name: "Auto-Ponte",       cost: 8,  effect: "auto_click",          value: 1,    unlocked: false, requires: "double_ponte",     branch: "ponte", exclusive_with: "ponte_frenetique" },
+  // Tier 3 (exclusif)
+  { id: "ponte_frenetique", name: "Frénésie",            cost: 15,  effect: "click_multiplier",    value: 3,    unlocked: false, requires: "double_ponte",     branch: "ponte", exclusive_with: "concentration" },
+  { id: "concentration",    name: "Concentration",       cost: 15,  effect: "click_multiplier",    value: 4,    unlocked: false, requires: "double_ponte",     branch: "ponte", exclusive_with: "ponte_frenetique" },
+  // Tier 3 (parallèle)
   { id: "ponte_critique",   name: "Ponte Critique",      cost: 20,  effect: "crit_click_chance",   value: 0.05, unlocked: false, requires: "double_ponte",     branch: "ponte" },
+  // Tier 4
   { id: "maitre_pondeur",   name: "Maître Pondeur",      cost: 40,  effect: "click_multiplier",    value: 5,    unlocked: false, requires: "ponte_critique",   branch: "ponte" },
+  // Capstone
+  { id: "ponte_auto",       name: "Ponte Automatique",   cost: 200, effect: "auto_click_scaling",  value: 1,    unlocked: false, requires: "maitre_pondeur",   branch: "ponte", capstone: true },
+  // Post-capstone (repeatable)
+  { id: "ponte_post",       name: "+5% auto-ponte",      cost: 500, effect: "auto_click",          value: 0.05, unlocked: false, requires: "ponte_auto",       branch: "ponte", repeatable: true, purchased: 0 },
 
-  // --- Marais (production) ---
+  // ═══ MARAIS (production) — 10 nœuds ═══
-  { id: "instinct_gregaire", name: "Instinct Grégaire",  cost: 1,  effect: "production_multiplier", value: 1.5,  unlocked: false, requires: null,                 branch: "marais" },
-  { id: "symbiose_algale",   name: "Symbiose Algale",    cost: 3,  effect: "generator_boost",       value: 2,    unlocked: false, requires: "instinct_gregaire",  branch: "marais" },
-  { id: "courant_profond",   name: "Courant Profond",    cost: 8,  effect: "production_multiplier", value: 2,    unlocked: false, requires: "symbiose_algale",    branch: "marais", exclusive_with: "maree_haute" },
-  { id: "maree_haute",       name: "Marée Haute",        cost: 8,  effect: "cost_reduction",        value: 0.20, unlocked: false, requires: "symbiose_algale",    branch: "marais", exclusive_with: "courant_profond" },
-  { id: "ecosysteme_mature", name: "Écosystème Mature",  cost: 20, effect: "production_multiplier", value: 3,    unlocked: false, requires: "courant_profond",    branch: "marais" },
-  { id: "marais_eternel",    name: "Marais Éternel",     cost: 40, effect: "production_multiplier", value: 5,    unlocked: false, requires: "ecosysteme_mature",  branch: "marais" },
 
-  // --- Adaptation (utility) ---
+  // Tier 1
-  { id: "memoire_genetique", name: "Mémoire Génétique",  cost: 1,  effect: "start_bonus",                  value: 100,  unlocked: false, requires: null,                  branch: "adaptation" },
+  { id: "instinct_gregaire", name: "Instinct Grégaire",  cost: 3,   effect: "production_multiplier", value: 1.5,  unlocked: false, requires: null,                 branch: "marais" },
-  { id: "adn_renforce",      name: "ADN Renforcé",       cost: 3,  effect: "prestige_dna_bonus",            value: 0.25, unlocked: false, requires: "memoire_genetique",   branch: "adaptation" },
+  // Tier 2
-  { id: "eveil_rapide",      name: "Éveil Rapide",       cost: 8,  effect: "offline_boost",                 value: 0.50, unlocked: false, requires: "adn_renforce",        branch: "adaptation", exclusive_with: "resilience" },
+  { id: "symbiose_algale",   name: "Symbiose Algale",    cost: 8,   effect: "generator_boost",       value: 2,    unlocked: false, requires: "instinct_gregaire",  branch: "marais" },
-  { id: "resilience",        name: "Résilience",         cost: 8,  effect: "unlock_generator",              value: 0,    unlocked: false, requires: "adn_renforce",        branch: "adaptation", exclusive_with: "eveil_rapide" },
+  // Tier 3 (exclusif)
-  { id: "heritage",          name: "Héritage",           cost: 20, effect: "prestige_dna_bonus",            value: 0.50, unlocked: false, requires: "eveil_rapide",        branch: "adaptation" },
+  { id: "courant_profond",   name: "Courant Profond",    cost: 25,  effect: "production_multiplier", value: 2,    unlocked: false, requires: "symbiose_algale",    branch: "marais", exclusive_with: "maree_haute" },
-  { id: "transcendance",     name: "Transcendance",      cost: 40, effect: "prestige_threshold_reduction",  value: 0.50, unlocked: false, requires: "heritage",            branch: "adaptation" },
+  { id: "maree_haute",       name: "Marée Haute",        cost: 25,  effect: "cost_reduction",        value: 0.20, unlocked: false, requires: "symbiose_algale",    branch: "marais", exclusive_with: "courant_profond" },
+  // Tier 3 (parallèle)
+  { id: "ecosysteme_mature", name: "Écosystème Mature",  cost: 25,  effect: "production_multiplier", value: 3,    unlocked: false, requires: "symbiose_algale",    branch: "marais" },
+  // Tier 4
+  { id: "marais_eternel",    name: "Marais Éternel",     cost: 60,  effect: "production_multiplier", value: 5,    unlocked: false, requires: "ecosysteme_mature",  branch: "marais" },
+  // Capstone
+  { id: "symbiose_totale",   name: "Symbiose Totale",    cost: 300, effect: "generator_synergy",     value: 0.02, unlocked: false, requires: "marais_eternel",     branch: "marais", capstone: true },
+  // Post-capstone (repeatable)
+  { id: "marais_post",       name: "+1% synergie",       cost: 600, effect: "generator_synergy",     value: 0.01, unlocked: false, requires: "symbiose_totale",    branch: "marais", repeatable: true, purchased: 0 },
+
+  // ═══ ADAPTATION (utility) — 10 nœuds ═══
+
+  // Tier 1
+  { id: "memoire_genetique", name: "Mémoire Génétique",  cost: 2,   effect: "start_bonus",                  value: 100,  unlocked: false, requires: null,                  branch: "adaptation" },
+  // Tier 2
+  { id: "adn_renforce",      name: "ADN Renforcé",       cost: 10,  effect: "prestige_dna_bonus",            value: 0.25, unlocked: false, requires: "memoire_genetique",   branch: "adaptation" },
+  // Tier 3 (exclusif)
+  { id: "eveil_rapide",      name: "Éveil Rapide",       cost: 30,  effect: "offline_boost",                 value: 0.50, unlocked: false, requires: "adn_renforce",        branch: "adaptation", exclusive_with: "mutation_adn" },
+  { id: "mutation_adn",      name: "Mutation ADN",       cost: 30,  effect: "prestige_dna_bonus",            value: 0.25, unlocked: false, requires: "adn_renforce",        branch: "adaptation", exclusive_with: "eveil_rapide" },
+  // Tier 3 (parallèle)
+  { id: "heritage",          name: "Héritage",           cost: 30,  effect: "prestige_dna_bonus",            value: 0.50, unlocked: false, requires: "adn_renforce",        branch: "adaptation" },
+  // Tier 4
+  { id: "transcendance",     name: "Transcendance",      cost: 60,  effect: "prestige_threshold_reduction",  value: 0.50, unlocked: false, requires: "heritage",            branch: "adaptation" },
+  // Capstone
+  { id: "memoire_marais",    name: "Mémoire du Marais",  cost: 250, effect: "offline_cap_boost",             value: 0.75, unlocked: false, requires: "transcendance",       branch: "adaptation", capstone: true },
+  // Post-capstone (repeatable)
+  { id: "adapt_post",        name: "+2% offline cap",    cost: 500, effect: "offline_boost",                 value: 0.02, unlocked: false, requires: "memoire_marais",      branch: "adaptation", repeatable: true, purchased: 0 },
+
+  // ═══ CROSS-BRANCHE — Convergence (nœud évolutif) ═══
+
+  { id: "convergence",       name: "Convergence",        cost: 500, effect: "all_effects_boost",  value: 0.10, unlocked: false, requires: null, branch: "cross",
+    tier: 1, maxTier: 2, tierUpgradeCost: 500, tierUpgradeRequires: "2_capstones" },
 ];
 
-// Calcule l'ADN gagné lors d'un prestige : floor(150 × sqrt(lifetime / 1e9))
+// Formule ADN Sprint 3 : max(1, floor(base × log10(t / threshold) × (1 + bonus)))
-export function computePrestigeDna(lifetimeTadpoles: number): number {
+// Clamp min 1 si seuil atteint, cap bonus ×4 à 80 prestiges
-  return Math.floor(150 * Math.sqrt(lifetimeTadpoles / 1e9));
+
+export function computePrestigeDna(lifetimeTadpoles: number, prestigeCount: number = 0): number {
+  if (lifetimeTadpoles < PRESTIGE_ADN_THRESHOLD) return 0;
+  const ratio = lifetimeTadpoles / PRESTIGE_ADN_THRESHOLD;
+  if (ratio <= 1) return PRESTIGE_ADN_MIN;
+  const bonus = Math.min(PRESTIGE_BONUS_PER_PRESTIGE * prestigeCount, PRESTIGE_BONUS_CAP);
+  const raw = PRESTIGE_ADN_BASE * Math.log10(ratio) * (1 + bonus);
+  return Math.max(PRESTIGE_ADN_MIN, Math.floor(raw));
+}
+
+// --- Milestones prestige ---
+
+// Milestones disponibles mais pas encore réclamés
+export function getClaimableMilestones(state: GameState): PrestigeMilestone[] {
+  return PRESTIGE_MILESTONES.filter(
+    (m) => state.prestigeCount >= m.threshold && !state.claimedMilestones.includes(m.id)
+  );
+}
+
+// Prochain milestone non atteint
+export function getNextMilestone(state: GameState): PrestigeMilestone | null {
+  return PRESTIGE_MILESTONES.find((m) => state.prestigeCount < m.threshold) ?? null;
+}
+
+// Réclamer un milestone
+export function claimMilestone(state: GameState, milestoneId: string): GameState | null {
+  const milestone = PRESTIGE_MILESTONES.find((m) => m.id === milestoneId);
+  if (!milestone) return null;
+  if (state.prestigeCount < milestone.threshold) return null;
+  if (state.claimedMilestones.includes(milestoneId)) return null;
+
+  let newState = {
+    ...state,
+    claimedMilestones: [...state.claimedMilestones, milestoneId],
+  };
+
+  // Appliquer la récompense
+  if (milestone.reward.type === "cosmetic") {
+    if (!newState.cosmeticInventory.includes(milestone.reward.cosmeticId)) {
+      newState = {
+        ...newState,
+        cosmeticInventory: [...newState.cosmeticInventory, milestone.reward.cosmeticId],
+      };
+    }
+  }
+  // Les bonus gameplay sont appliqués passivement via getMilestoneBonus()
+
+  return newState;
+}
+
+// Bonus gameplay cumulés depuis les milestones réclamés
+export function getMilestoneStartNid(state: GameState): number {
+  const claimed = state.claimedMilestones;
+  if (claimed.includes("milestone_5")) return 1; // 1 Nid gratuit
+  return 0;
+}
+
+export function getMilestoneOfflineBonus(state: GameState): number {
+  const claimed = state.claimedMilestones;
+  if (claimed.includes("milestone_15")) return 0.05; // +5% offline cap
+  return 0;
+}
+
+// Compte les capstones débloqués
+export function getUnlockedCapstoneCount(tree: EvolutionNode[]): number {
+  return tree.filter((n) => n.capstone && n.unlocked).length;
+}
+
+// Coût actuel d'un nœud repeatable (scaling par tranche via balance.ts)
+export function getRepeatableCost(node: EvolutionNode): number {
+  if (!node.repeatable) return node.cost;
+  return postCapstoneCost(node.cost, node.purchased ?? 0);
+}
+
+// Vérifie si le joueur peut acheter Convergence (condition spéciale)
+function canBuyConvergence(state: GameState, node: EvolutionNode): boolean {
+  // Tier 1 : 1 capstone + au moins 1 nœud tier 3 d'une 2e branche
+  if (!node.unlocked && (node.tier ?? 1) === 1) {
+    const capstones = getUnlockedCapstoneCount(state.evolutionTree);
+    if (capstones < 1) return false;
+    // Check: au moins 1 nœud dans une branche différente de la capstone
+    const capstoneBranches = new Set(
+      state.evolutionTree.filter((n) => n.capstone && n.unlocked).map((n) => n.branch)
+    );
+    const otherBranchNodes = state.evolutionTree.filter(
+      (n) => n.unlocked && !capstoneBranches.has(n.branch) && n.branch !== "cross" && n.cost >= 15
+    );
+    return otherBranchNodes.length > 0 && state.ancestralDna >= node.cost;
+  }
+  return false;
+}
+
+// Vérifie si Convergence peut être upgradé au tier suivant
+export function canUpgradeConvergence(state: GameState): boolean {
+  const conv = state.evolutionTree.find((n) => n.id === "convergence");
+  if (!conv || !conv.unlocked) return false;
+  if ((conv.tier ?? 1) >= (conv.maxTier ?? 2)) return false;
+  if (conv.tierUpgradeRequires === "2_capstones" && getUnlockedCapstoneCount(state.evolutionTree) < 2) return false;
+  return state.ancestralDna >= (conv.tierUpgradeCost ?? 500);
+}
+
+// Upgrade Convergence au tier suivant
+export function upgradeConvergence(state: GameState): GameState | null {
+  if (!canUpgradeConvergence(state)) return null;
+  const conv = state.evolutionTree.find((n) => n.id === "convergence")!;
+  const cost = conv.tierUpgradeCost ?? 500;
+  return {
+    ...state,
+    ancestralDna: state.ancestralDna - cost,
+    evolutionTree: state.evolutionTree.map((n) =>
+      n.id === "convergence"
+        ? { ...n, tier: (n.tier ?? 1) + 1, effect: "post_capstone_discount" as EffectType, value: 0.20 }
+        : n
+    ),
+  };
 }
 
 // Vérifie si un nœud peut être acheté
 export function canBuyEvolutionNode(state: GameState, nodeId: string): boolean {
   const node = state.evolutionTree.find((n) => n.id === nodeId);
-  if (!node || node.unlocked) return false;
+  if (!node) return false;
-  if (state.ancestralDna < node.cost) return false;
+
+  // Convergence a sa propre logique
+  if (node.id === "convergence") return canBuyConvergence(state, node);
+
+  // Repeatable : toujours achetable si unlocked + prérequis + assez d'ADN
+  if (node.repeatable && node.unlocked) {
+    const cost = getRepeatableCost(node);
+    return state.ancestralDna >= cost;
+  }
+
+  if (node.unlocked) return false;
+
+  const cost = node.repeatable ? getRepeatableCost(node) : node.cost;
+  if (state.ancestralDna < cost) return false;
+
   if (node.requires) {
     const prereq = state.evolutionTree.find((n) => n.id === node.requires);
     if (!prereq || !prereq.unlocked) return false;
@@ -111,31 +325,80 @@ export function buyEvolutionNode(state: GameState, nodeId: string): GameState |
   if (!canBuyEvolutionNode(state, nodeId)) return null;
 
   const node = state.evolutionTree.find((n) => n.id === nodeId)!;
+
+  // Repeatable node — already unlocked, increment purchased
+  if (node.repeatable && node.unlocked) {
+    const cost = getRepeatableCost(node);
     return {
       ...state,
-    ancestralDna: state.ancestralDna - node.cost,
+      ancestralDna: state.ancestralDna - cost,
+      evolutionTree: state.evolutionTree.map((n) =>
+        n.id === nodeId ? { ...n, purchased: (n.purchased ?? 0) + 1 } : n
+      ),
+    };
+  }
+
+  const cost = node.repeatable ? getRepeatableCost(node) : node.cost;
+  return {
+    ...state,
+    ancestralDna: state.ancestralDna - cost,
     evolutionTree: state.evolutionTree.map((n) =>
       n.id === nodeId ? { ...n, unlocked: true } : n
     ),
   };
 }
 
-// Reset l'arbre — rembourse tout l'ADN dépensé, relock tous les nœuds
+// Coût du prochain reset arbre (pour affichage UI)
+export function getTreeResetCost(state: GameState): number {
+  return treeResetCost(state.freeResetAvailable, state.extraResetsUsed);
+}
+
+// Vérifie si le joueur peut reset l'arbre
+export function canResetTree(state: GameState): boolean {
+  if (state.prestigeCount < 1) return false;
+  const cost = getTreeResetCost(state);
+  return state.ancestralDna >= cost;
+}
+
+// Reset l'arbre — rembourse l'ADN dépensé (y compris repeatables), déduit le coût du reset
 export function resetEvolutionTree(state: GameState): GameState {
-  const spentDna = state.evolutionTree
+  const cost = getTreeResetCost(state);
-    .filter((n) => n.unlocked)
+  if (state.ancestralDna < cost) return state;
-    .reduce((sum, n) => sum + n.cost, 0);
+
+  const spentDna = getSpentDna(state.evolutionTree);
 
   return {
     ...state,
-    ancestralDna: state.ancestralDna + spentDna,
+    ancestralDna: state.ancestralDna + spentDna - cost,
-    evolutionTree: state.evolutionTree.map((n) => ({ ...n, unlocked: false })),
+    evolutionTree: state.evolutionTree.map((n) => ({
+      ...n,
+      unlocked: false,
+      purchased: n.repeatable ? 0 : n.purchased,
+      tier: n.maxTier ? 1 : n.tier,
+    })),
+    freeResetAvailable: state.freeResetAvailable ? false : state.freeResetAvailable,
+    extraResetsUsed: state.freeResetAvailable ? state.extraResetsUsed : state.extraResetsUsed + 1,
   };
 }
 
-// Compte l'ADN total investi dans l'arbre
+// Compte l'ADN total investi dans l'arbre (standard + repeatables + convergence upgrades)
 export function getSpentDna(tree: EvolutionNode[]): number {
-  return tree.filter((n) => n.unlocked).reduce((sum, n) => sum + n.cost, 0);
+  let total = 0;
+  for (const n of tree) {
+    if (!n.unlocked) continue;
+    total += n.cost; // coût initial
+    // Repeatables : somme des coûts de chaque achat
+    if (n.repeatable && (n.purchased ?? 0) > 0) {
+      for (let i = 0; i < n.purchased!; i++) {
+        total += postCapstoneCost(n.cost, i);
+      }
+    }
+    // Convergence tier upgrades
+    if (n.maxTier && (n.tier ?? 1) > 1) {
+      total += (n.tierUpgradeCost ?? 0) * ((n.tier ?? 1) - 1);
+    }
+  }
+  return total;
 }
 
 // Calcule le multiplicateur click total depuis l'arbre
@@ -166,11 +429,13 @@ export function getDoubleClickChance(tree: EvolutionNode[]): number {
     .reduce((sum, n) => sum + n.value, 0);
 }
 
-// Auto-clicks par seconde depuis l'arbre
+// Auto-clicks par seconde depuis l'arbre (standard + capstone scaling)
 export function getAutoClicksPerSecond(tree: EvolutionNode[]): number {
-  return tree
+  const standard = tree
-    .filter((n) => n.unlocked && n.effect === "auto_click")
+    .filter((n) => n.unlocked && n.effect === "auto_click" && !n.repeatable)
     .reduce((sum, n) => sum + n.value, 0);
+  const scaling = getAutoClickScaling(tree);
+  return standard + scaling;
 }
 
 // Chance de crit click (0-1), crit = x10
@@ -215,13 +480,48 @@ export function getPrestigeThresholdReduction(tree: EvolutionNode[]): number {
     .reduce((sum, n) => sum + n.value, 0);
 }
 
-// --- Offline gains (courbe inversée) ---
+// --- Sprint 3 — Nouveaux effets ---
 
-const OFFLINE_THRESHOLD = 60_000; // 60s — en-dessous = idle normal, au-dessus = offline
+// Ponte Automatique (capstone) : 1 auto-click/s de base, scale avec les repeatables
-const OFFLINE_FULL_MS = 15 * 60_000; // 0-15min : 100%
+export function getAutoClickScaling(tree: EvolutionNode[]): number {
-const OFFLINE_DECAY_END_MS = 60 * 60_000; // 15min-1h : 100% → 25%
+  const capstone = tree.find((n) => n.id === "ponte_auto" && n.unlocked);
-const OFFLINE_ZERO_MS = 2 * 60 * 60_000; // 1h-2h : 25% → 0%
+  if (!capstone) return 0;
-const OFFLINE_FLOOR = 0.25; // plancher de la phase de decay
+  const baseAutoClick = capstone.value; // 1/s
+  // Post-capstone adds flat auto-click value per purchase
+  const postNode = tree.find((n) => n.id === "ponte_post" && n.unlocked);
+  const postBonus = postNode ? postNode.value * (postNode.purchased ?? 0) : 0;
+  return baseAutoClick + postBonus;
+}
+
+// Symbiose Totale (capstone) : +X% par type de générateur possédé
+// Retourne le multiplicateur (ex: 5 types × 0.02 = 0.10 → ×1.10)
+export function getGeneratorSynergyMultiplier(tree: EvolutionNode[], generators: Generator[]): number {
+  const synergyNodes = tree.filter((n) => n.unlocked && n.effect === "generator_synergy");
+  if (synergyNodes.length === 0) return 1;
+  const totalSynergyRate = synergyNodes.reduce((sum, n) => {
+    // For repeatables, each purchase adds to the rate
+    const extra = n.repeatable ? n.value * (n.purchased ?? 0) : 0;
+    return sum + n.value + extra;
+  }, 0);
+  const typesOwned = generators.filter((g) => g.owned > 0).length;
+  return 1 + totalSynergyRate * typesOwned;
+}
+
+// Convergence : all_effects_boost — multiplicateur global sur tous les effets de l'arbre
+export function getAllEffectsBoost(tree: EvolutionNode[]): number {
+  const conv = tree.find((n) => n.id === "convergence" && n.unlocked);
+  if (!conv) return 1;
+  return 1 + conv.value; // 0.10 = ×1.10
+}
+
+// Convergence Omega : post_capstone_discount
+export function getPostCapstoneDiscount(tree: EvolutionNode[]): number {
+  const conv = tree.find((n) => n.id === "convergence" && n.unlocked && n.effect === "post_capstone_discount");
+  if (!conv) return 0;
+  return conv.value; // 0.20 = -20%
+}
+
+// --- Offline gains (courbe inversée) ---
 
 // Retourne le multiplicateur d'efficacité offline (1.0 → 0.0)
 // basé sur le temps d'absence en ms
@@ -250,7 +550,7 @@ export function computeOfflineGains(state: GameState, now: number): number {
   const pps = totalProductionPerSecond(state);
   if (pps <= 0) return 0;
 
-  const offlineBoost = 1 + getOfflineBoost(state.evolutionTree);
+  const offlineBoost = 1 + getOfflineBoost(state.evolutionTree) + getMilestoneOfflineBonus(state);
 
   // Intégration par tranches de 60s
   const STEP = 60_000;
@@ -276,6 +576,7 @@ export function generatorCost(gen: Generator, tree?: EvolutionNode[]): number {
 // Production totale par seconde de tous les générateurs
 export function totalProductionPerSecond(state: GameState): number {
   const nidBoost = getGeneratorBoostFromTree(state.evolutionTree);
+  const synergyMult = getGeneratorSynergyMultiplier(state.evolutionTree, state.generators);
   const base = state.generators.reduce(
     (sum, gen) => {
       const boost = gen.id === "nid" ? nidBoost : 1;
@@ -284,7 +585,8 @@ export function totalProductionPerSecond(state: GameState): number {
     0
   );
   const treeMultiplier = getProductionMultiplierFromTree(state.evolutionTree);
-  return base * state.prestigeMultiplier * treeMultiplier;
+  const convergenceBoost = getAllEffectsBoost(state.evolutionTree);
+  return base * state.prestigeMultiplier * treeMultiplier * synergyMult * convergenceBoost;
 }
 
 // Lazy calculation : ressources accumulées depuis lastTick
@@ -301,6 +603,10 @@ export function applyIdleGains(state: GameState, now: number): GameState {
     resources: state.resources + gains,
     lifetimeTadpoles: state.lifetimeTadpoles + gains,
     lastTick: now,
+    runStats: {
+      ...state.runStats,
+      tadpolesProduced: state.runStats.tadpolesProduced + gains,
+    },
   };
 }
 
@@ -342,6 +648,10 @@ export function applyClick(state: GameState, rng: number = Math.random()): Click
       ...state,
       resources: state.resources + gain,
       lifetimeTadpoles: state.lifetimeTadpoles + gain,
+      runStats: {
+        ...state.runStats,
+        tadpolesProduced: state.runStats.tadpolesProduced + gain,
+      },
     },
     gain,
     isDouble,
@@ -369,7 +679,6 @@ export function buyGenerator(state: GameState, genId: string): GameState | null
 }
 
 // Prestige : reset run, gain ADN, arbre persiste
-const BASE_PRESTIGE_THRESHOLD = 1_000_000;
 
 export function getPrestigeThreshold(state: GameState): number {
   const reduction = getPrestigeThresholdReduction(state.evolutionTree);
@@ -383,7 +692,7 @@ export function canPrestige(state: GameState): boolean {
 export function applyPrestige(state: GameState): GameState {
   const newPrestigeCount = state.prestigeCount + 1;
   const dnaBonus = getPrestigeDnaBonus(state.evolutionTree);
-  const baseDna = computePrestigeDna(state.lifetimeTadpoles);
+  const baseDna = computePrestigeDna(state.lifetimeTadpoles, state.prestigeCount);
   const dnaGained = Math.floor(baseDna * (1 + dnaBonus));
   const startBonus = getStartBonusFromTree(state.evolutionTree);
 
@@ -391,20 +700,42 @@ export function applyPrestige(state: GameState): GameState {
   const hasUnlockGen = state.evolutionTree.some(
     (n) => n.unlocked && n.effect === "unlock_generator"
   );
+  // Milestone bonus : Nid gratuit au départ
+  const milestoneNid = getMilestoneStartNid(state);
+
+  // RunStats : snapshot de la run qui se termine
+  const now = Date.now();
+  const runDuration = now - state.runStats.startedAt;
+  const bestRun = state.runStats.bestRun;
+  const newBestRun =
+    !bestRun || dnaGained > bestRun.adn
+      ? { duration: runDuration, tadpoles: state.lifetimeTadpoles, adn: dnaGained }
+      : bestRun;
 
   return {
     ...state,
     resources: startBonus,
     generators: state.generators.map((g) => ({
       ...g,
-      owned: hasUnlockGen && g.id === "lac" ? 1 : 0,
+      owned:
+        (hasUnlockGen && g.id === "lac") ? 1 :
+        (milestoneNid > 0 && g.id === "nid") ? milestoneNid :
+        0,
     })),
     prestigeCount: newPrestigeCount,
     prestigeMultiplier: 1 + newPrestigeCount * 0.1,
     ancestralDna: state.ancestralDna + dnaGained,
     lifetimeTadpoles: 0,
-    lastTick: Date.now(),
+    lastTick: now,
-    lastOnline: Date.now(),
+    lastOnline: now,
+    // Sprint 3 — nouvelle run
+    runStats: {
+      startedAt: now,
+      tadpolesProduced: 0,
+      bestRun: newBestRun,
+    },
+    freeResetAvailable: true,  // 1 reset gratuit offert par prestige
+    extraResetsUsed: 0,
     // evolutionTree persiste — jamais reset
   };
 }
@@ -419,6 +750,7 @@ export const DEFAULT_GENERATORS: Generator[] = [
 ];
 
 export const DEFAULT_STATE: GameState = {
+  saveVersion: CURRENT_SAVE_VERSION,
   resources: 0,
   clickMultiplier: 1,
   generators: DEFAULT_GENERATORS,
@@ -431,4 +763,12 @@ export const DEFAULT_STATE: GameState = {
   lifetimeTadpoles: 0,
   cosmeticInventory: [],
   cosmeticEquipped: {},
+  runStats: {
+    startedAt: Date.now(),
+    tadpolesProduced: 0,
+    bestRun: null,
+  },
+  freeResetAvailable: true,
+  extraResetsUsed: 0,
+  claimedMilestones: [],
 };

Frontend/src/core/migrateSave.ts

@@ -0,0 +1,142 @@
+// migrateSave.ts — Migration lazy des saves entre versions
+// Appliqué au chargement (frontend + backend). Jamais de migration en DB.
+// Chaque sprint ajoute un step (v2→v3, etc.)
+
+import { CURRENT_SAVE_VERSION } from "./balance";
+import type { GameState } from "./economy";
+import { DEFAULT_EVOLUTION_TREE, DEFAULT_GENERATORS } from "./economy";
+
+/**
+ * Détecte la version d'une save et applique les migrations nécessaires.
+ * Entrée : objet brut depuis la DB/localStorage (potentiellement incomplet).
+ * Sortie : GameState conforme à la version courante.
+ */
+export function migrateSave(raw: Record<string, unknown>): GameState {
+  const version = typeof raw.saveVersion === "number" ? raw.saveVersion : 1;
+
+  let state = raw as Record<string, unknown>;
+
+  if (version < 2) {
+    state = migrateV1toV2(state);
+  }
+
+  // Futures migrations :
+  // if (version < 3) state = migrateV2toV3(state);
+
+  return state as unknown as GameState;
+}
+
+/**
+ * v1 → v2 : Sprint 2 → Sprint 3
+ * - Ajoute saveVersion
+ * - Ajoute runStats (vide)
+ * - Ajoute freeResetAvailable + extraResetsUsed
+ * - Merge les nouveaux nœuds arbre (conserve l'état des 18 existants)
+ * - Backfill champs manquants (cosmeticInventory, cosmeticEquipped, lastOnline)
+ */
+function migrateV1toV2(raw: Record<string, unknown>): Record<string, unknown> {
+  const state = { ...raw };
+
+  // saveVersion
+  state.saveVersion = 2;
+
+  // RunStats (nouveau Sprint 3)
+  if (!state.runStats) {
+    state.runStats = {
+      startedAt: typeof state.lastTick === "number" ? state.lastTick : Date.now(),
+      tadpolesProduced: 0,
+      bestRun: null,
+    };
+  }
+
+  // Reset arbre : 1 gratuit par prestige
+  if (typeof state.freeResetAvailable !== "boolean") {
+    state.freeResetAvailable = true;
+  }
+  if (typeof state.extraResetsUsed !== "number") {
+    state.extraResetsUsed = 0;
+  }
+
+  // Milestones (Sprint 3)
+  if (!Array.isArray(state.claimedMilestones)) {
+    state.claimedMilestones = [];
+  }
+
+  // Backfill champs Sprint 2 potentiellement manquants
+  if (!state.lastOnline) state.lastOnline = state.lastTick;
+  if (!Array.isArray(state.cosmeticInventory)) state.cosmeticInventory = [];
+  if (!state.cosmeticEquipped || typeof state.cosmeticEquipped !== "object") {
+    state.cosmeticEquipped = {};
+  }
+
+  // Merge arbre : conserver les 18 nœuds existants + ajouter les nouveaux
+  state.evolutionTree = mergeEvolutionTree(
+    state.evolutionTree as Array<Record<string, unknown>> | undefined
+  );
+
+  // Merge générateurs : conserver owned + ajouter les potentiels nouveaux
+  state.generators = mergeGenerators(
+    state.generators as Array<Record<string, unknown>> | undefined
+  );
+
+  return state;
+}
+
+/**
+ * Merge l'arbre sauvegardé avec DEFAULT_EVOLUTION_TREE.
+ * - Nœuds existants : conserve unlocked state
+ * - Nœuds nouveaux : ajoutés avec unlocked: false
+ * - Nœuds supprimés du default : retirés (forward compat)
+ */
+function mergeEvolutionTree(
+  savedTree: Array<Record<string, unknown>> | undefined
+): typeof DEFAULT_EVOLUTION_TREE {
+  if (!savedTree || !Array.isArray(savedTree)) {
+    return DEFAULT_EVOLUTION_TREE.map((n) => ({ ...n }));
+  }
+
+  const savedById = new Map(
+    savedTree.map((n) => [n.id as string, n])
+  );
+
+  return DEFAULT_EVOLUTION_TREE.map((defaultNode) => {
+    const saved = savedById.get(defaultNode.id);
+    if (saved) {
+      // Conserver l'état unlocked, tout le reste vient du default
+      // (permet de corriger des valeurs rebalancées sans casser les saves)
+      return {
+        ...defaultNode,
+        unlocked: saved.unlocked === true,
+      };
+    }
+    // Nouveau nœud — ajouté verrouillé
+    return { ...defaultNode };
+  });
+}
+
+/**
+ * Merge les générateurs sauvegardés avec DEFAULT_GENERATORS.
+ * Conserve le owned count, met à jour les stats de base.
+ */
+function mergeGenerators(
+  savedGens: Array<Record<string, unknown>> | undefined
+): typeof DEFAULT_GENERATORS {
+  if (!savedGens || !Array.isArray(savedGens)) {
+    return DEFAULT_GENERATORS.map((g) => ({ ...g }));
+  }
+
+  const savedById = new Map(
+    savedGens.map((g) => [g.id as string, g])
+  );
+
+  return DEFAULT_GENERATORS.map((defaultGen) => {
+    const saved = savedById.get(defaultGen.id);
+    if (saved) {
+      return {
+        ...defaultGen,
+        owned: typeof saved.owned === "number" ? saved.owned : 0,
+      };
+    }
+    return { ...defaultGen };
+  });
+}

Frontend/src/data/prestigeMilestones.ts

@@ -0,0 +1,76 @@
+// prestigeMilestones.ts — Paliers de prestige (Sprint 3)
+// 8 paliers : cosmétiques exclusifs + bonus gameplay légers
+
+export type MilestoneRewardType = "cosmetic" | "bonus" | "title";
+
+export interface PrestigeMilestone {
+  id: string;
+  threshold: number;        // nombre de prestiges requis
+  name: string;
+  description: string;
+  reward: MilestoneReward;
+}
+
+export type MilestoneReward =
+  | { type: "cosmetic"; cosmeticId: string; label: string }
+  | { type: "bonus"; effect: string; value: number; label: string }
+  | { type: "title"; title: string; label: string };
+
+export const PRESTIGE_MILESTONES: PrestigeMilestone[] = [
+  {
+    id: "milestone_1",
+    threshold: 1,
+    name: "Premiere Generation",
+    description: "Premier prestige accompli",
+    reward: { type: "cosmetic", cosmeticId: "ribbon", label: "Ruban queue" },
+  },
+  {
+    id: "milestone_3",
+    threshold: 3,
+    name: "Gardien Recurrent",
+    description: "3 prestiges — la perseverance paie",
+    reward: { type: "title", title: "Gardien Recurrent", label: "Titre exclusif" },
+  },
+  {
+    id: "milestone_5",
+    threshold: 5,
+    name: "Nid Offert",
+    description: "5 prestiges — un coup de pouce au depart",
+    reward: { type: "bonus", effect: "start_nid", value: 1, label: "1 Nid gratuit au depart" },
+  },
+  {
+    id: "milestone_10",
+    threshold: 10,
+    name: "Tetard Ancestral",
+    description: "10 prestiges — la lignee s'affirme",
+    reward: { type: "cosmetic", cosmeticId: "crown", label: "Couronne doree + skin Ancestral" },
+  },
+  {
+    id: "milestone_15",
+    threshold: 15,
+    name: "Marais Fidele",
+    description: "15 prestiges — le marais te reconnait",
+    reward: { type: "bonus", effect: "offline_cap_perm", value: 0.05, label: "+5% offline cap permanent" },
+  },
+  {
+    id: "milestone_25",
+    threshold: 25,
+    name: "Gardien Emerite",
+    description: "25 prestiges — tissu d'algues ancestrales",
+    reward: { type: "cosmetic", cosmeticId: "cape_algae", label: "Cape d'algues ancestrales" },
+  },
+  {
+    id: "milestone_50",
+    threshold: 50,
+    name: "Legende du Marais",
+    description: "50 prestiges — la legende est toi",
+    reward: { type: "cosmetic", cosmeticId: "flame_tail", label: "Queue enflamee + particules dorees" },
+  },
+  {
+    id: "milestone_100",
+    threshold: 100,
+    name: "Tetard Primordial",
+    description: "100 prestiges — retour aux origines",
+    reward: { type: "cosmetic", cosmeticId: "primordial_body", label: "Skin Tetard Primordial (full set)" },
+  },
+];

Frontend/src/hooks/useSaveSync.ts

@@ -5,6 +5,7 @@ import { useEffect, useRef, useCallback, useState } from "react";
 import { useAuth } from "../context/AuthContext";
 import { useGameStore } from "../store/useGameStore";
 import type { GameState } from "../core/economy";
+import { migrateSave } from "../core/migrateSave";
 
 const SAVE_INTERVAL_MS = 30_000; // 30 seconds
 const BACKEND_URL = import.meta.env.VITE_BACKEND_URL || "http://localhost:3310";
@@ -51,9 +52,10 @@ export function useSaveSync({ getGameState, onLoad, playTimeSeconds }: SaveSyncO
 
     apiRequest("/save").then((data) => {
       if (data?.gameState) {
-        onLoad(data.gameState);
+        const migrated = migrateSave(data.gameState);
+        onLoad(migrated);
         lastSaveRef.current = data.lastSave;
-        console.info("[SaveSync] Loaded save from server — server is authority");
+        console.info("[SaveSync] Loaded save from server — server is authority (v%d)", migrated.saveVersion);
       } else {
         console.info("[SaveSync] No server save found — starting fresh");
       }
@@ -99,7 +101,8 @@ export function useSaveSync({ getGameState, onLoad, playTimeSeconds }: SaveSyncO
       setTimeout(() => apiRequest("/save").then((data) => {
         if (data?.gameState && data.lastSave) {
           if (!lastSaveRef.current || new Date(data.lastSave) > new Date(lastSaveRef.current)) {
-            onLoad(data.gameState);
+            const migrated = migrateSave(data.gameState);
+            onLoad(migrated);
             lastSaveRef.current = data.lastSave;
             console.info("[SaveSync] Reloaded from server on focus");
           }

Frontend/src/pages/Home.jsx

@@ -12,6 +12,8 @@ import { MilestoneBar } from "../components/MilestoneBar";
 import { CockpitHeader } from "../components/CockpitHeader";
 import { TadpoleSprite } from "../components/TadpoleSprite";
 import { CosmeticsPanel } from "../components/CosmeticsPanel";
+import { PrestigeScreen } from "../components/PrestigeScreen";
+import { MilestonesPanel } from "../components/MilestonesPanel";
 import { ACHIEVEMENTS } from "../data/achievements";
 
 export default function Home() {
@@ -136,6 +138,8 @@ export default function Home() {
         <title>Clickerz — Tetard Universe</title>
       </Helmet>
 
+      <PrestigeScreen />
+
       {/* Clicker area — centre */}
       <div className="click-zone" onClick={handleIncrement}>
         <TadpoleSprite />
@@ -152,6 +156,7 @@ export default function Home() {
         <GeneratorShop />
         <div className="gp-sep" />
         <PrestigePanel />
+        <MilestonesPanel />
         <EvolutionTree />
         <CosmeticsPanel />
         <a href="/achievements" className="achieve-badge">

Frontend/src/store/useGameStore.ts

@@ -13,6 +13,10 @@ import {
   buyGenerator,
   buyEvolutionNode,
   resetEvolutionTree,
+  canResetTree,
+  upgradeConvergence,
+  canUpgradeConvergence,
+  claimMilestone as claimMilestoneFn,
   applyPrestige,
   canPrestige as canPrestigeCheck,
   totalProductionPerSecond,
@@ -20,6 +24,7 @@ import {
   computeOfflineGains,
   offlineEfficiency,
 } from "../core/economy";
+import { migrateSave } from "../core/migrateSave";
 import {
   computeNewUnlocks,
   equipCosmetic as equipCosmeticFn,
@@ -36,11 +41,8 @@ function loadLocalState(): GameState {
   try {
     const raw = localStorage.getItem(SAVE_KEY);
     if (!raw) return { ...DEFAULT_STATE, lastTick: Date.now(), lastOnline: Date.now() };
-    const saved = JSON.parse(raw) as GameState;
+    const parsed = JSON.parse(raw);
-    // Backfill for old saves
+    const saved = migrateSave(parsed);
-    if (!saved.lastOnline) saved.lastOnline = saved.lastTick;
-    if (!saved.cosmeticInventory) saved.cosmeticInventory = [];
-    if (!saved.cosmeticEquipped) saved.cosmeticEquipped = {};
     return applyIdleGains(saved, Date.now());
   } catch {
     return { ...DEFAULT_STATE, lastTick: Date.now(), lastOnline: Date.now() };
@@ -68,6 +70,11 @@ interface GameStore {
   offlineReport: OfflineReport | null;
   dismissOfflineReport: () => void;
 
+  // Prestige screen (modal fullscreen)
+  showPrestigeScreen: boolean;
+  openPrestigeScreen: () => void;
+  closePrestigeScreen: () => void;
+
   // Last click result (for particle feedback)
   lastClickGain: number;
   lastClickDouble: boolean;
@@ -84,6 +91,8 @@ interface GameStore {
   buyNode: (nodeId: string) => void;
   prestige: () => void;
   resetTree: () => void;
+  upgradeConvergenceNode: () => void;
+  claimMilestone: (milestoneId: string) => void;
   equipCosmetic: (cosmeticId: string) => void;
   unequipCosmetic: (slot: CosmeticSlot) => void;
   reset: () => void;
@@ -94,11 +103,7 @@ interface GameStore {
 }
 
 function hydrateWithOffline(saved: GameState, now: number): { state: GameState; report: OfflineReport | null } {
-  // Backfill for old saves
+  // migrateSave handles backfill — no manual patching needed here
-  if (!saved.lastOnline) saved.lastOnline = saved.lastTick;
-  if (!saved.cosmeticInventory) saved.cosmeticInventory = [];
-  if (!saved.cosmeticEquipped) saved.cosmeticEquipped = {};
-
   const elapsed = now - saved.lastTick;
 
   if (elapsed <= OFFLINE_THRESHOLD) {
@@ -142,6 +147,9 @@ export const useGameStore = create<GameStore>((set, get) => ({
   playSeconds: 0,
   ready: false,
   offlineReport: null,
+  showPrestigeScreen: false,
+  openPrestigeScreen: () => set({ showPrestigeScreen: true }),
+  closePrestigeScreen: () => set({ showPrestigeScreen: false }),
   lastClickGain: 0,
   lastClickDouble: false,
   lastClickCrit: false,
@@ -238,6 +246,7 @@ export const useGameStore = create<GameStore>((set, get) => ({
         state: updated,
         canPrestige: canPrestigeCheck(updated),
         productionPerSecond: totalProductionPerSecond(updated),
+        showPrestigeScreen: false,
       };
     });
   },
@@ -267,6 +276,7 @@ export const useGameStore = create<GameStore>((set, get) => ({
   resetTree: () => {
     if (!get().ready) return;
     set((s) => {
+      if (!canResetTree(s.state)) return s;
       const updated = resetEvolutionTree(s.state);
       saveLocal(updated);
       return {
@@ -276,6 +286,29 @@ export const useGameStore = create<GameStore>((set, get) => ({
     });
   },
 
+  upgradeConvergenceNode: () => {
+    if (!get().ready) return;
+    set((s) => {
+      const updated = upgradeConvergence(s.state);
+      if (!updated) return s;
+      saveLocal(updated);
+      return {
+        state: updated,
+        productionPerSecond: totalProductionPerSecond(updated),
+      };
+    });
+  },
+
+  claimMilestone: (milestoneId: string) => {
+    if (!get().ready) return;
+    set((s) => {
+      const updated = claimMilestoneFn(s.state, milestoneId);
+      if (!updated) return s;
+      saveLocal(updated);
+      return { state: updated };
+    });
+  },
+
   reset: () => {
     const fresh = { ...DEFAULT_STATE, lastTick: Date.now(), lastOnline: Date.now() };
     saveLocal(fresh);
@@ -290,7 +323,8 @@ export const useGameStore = create<GameStore>((set, get) => ({
   },
 
   loadFromServer: (serverState: GameState) => {
-    const { state: hydrated, report } = hydrateWithOffline(serverState, Date.now());
+    const migrated = migrateSave(serverState as unknown as Record<string, unknown>);
+    const { state: hydrated, report } = hydrateWithOffline(migrated, Date.now());
     saveLocal(hydrated);
     set({
       state: hydrated,

docs/GDD.md

@@ -188,6 +188,43 @@ Brief technique : `docs/SPRINT2.md`
 
 ---
 
+## Sprint 3 — Prestige Loop (endless)
+
+Brief technique : `docs/SPRINT3.md`
+
+| Feature | Design |
+|---------|--------|
+| Migration saves | Pattern `saveVersion` + `migrateSave()` — backward compat Sprint 2, lazy au chargement |
+| Prestige Experience | Écran redesigné (preview ADN, stats run, comparaison), animation reset, hooks audio-ready |
+| Arbre V2 endless | ~30 nœuds (3 branches approfondies), capstones game-changers, post-capstone repeatable (scaling par tranche ×1.5/×1.8/×2.0), cross-branche |
+| Milestones prestige | 8 paliers (1→100 prestiges), cosmétiques exclusifs + bonus gameplay légers |
+| Reset arbre | 1 gratuit par prestige, payant linéaire au-delà (5 ADN × n). Build exportable (fondation Sprint 4 sharing) |
+| Formule ADN rebalancée | `max(1, floor(50 × log10(t/1e6) × (1 + min(0.05×p, 3.0))))` — clamp + cap bonus ×4 |
+
+### Capstones par branche
+
+| Branche | Capstone | Effet |
+|---------|----------|-------|
+| Ponte (click) | **Ponte Automatique** | Auto-click 1/sec, scale avec upgrades ponte |
+| Marais (production) | **Symbiose Totale** | Chaque générateur booste les autres (+2% par type possédé) |
+| Adaptation (utility) | **Mémoire du Marais** | Offline cap 25%→75%, durée 2h→8h |
+
+### Profils joueurs émergents
+
+- **Joueur Ponte** : joue activement, optimise les clics, capstone = auto-click idle
+- **Joueur Marais** : optimise les achats générateurs, capstone = boucle multiplicative
+- **Joueur Adaptation** : joue casual 2-3×/jour, capstone = idle puissant
+
+## Hors scope Sprint 3
+
+- Boucle 3 (méta, events, leaderboard, cross-promo TetaRdPG)
+- Son / musique (prévu Sprint 4+ — hooks audio posés dans prestige)
+- Mobile responsive / client natif Godot (projet séparé envisagé)
+- Monétisation effective (boutique cosmétique payante)
+- Analytics joueur (event log backend — Sprint 4)
+
+---
+
 ## Changelog
 
 | Date | Changement |
@@ -195,3 +232,5 @@ Brief technique : `docs/SPRINT2.md`
 | 2026-03-17 | GDD initial — sprint1-step1, stack React+TS+Vite, mécaniques core |
 | 2026-03-20 | Refonte game-designer — Tetard Universe, Arbre d'Évolution, anti-triche backend, SuperOAuth, stack confirmée Express |
 | 2026-03-28 | Sprint 1 livré (6/6). Sprint 2 briefé — offline gains courbe inversée, arbre 3 voies, cosmétiques récompenses |
+| 2026-03-28 | Sprint 2 livré (3/3). Sprint 3 briefé — prestige loop endless, arbre V2 30 nœuds, capstones, milestones, formule ADN rebalancée |
+| 2026-03-28 | Sprint 3 brainstorm — 5 décisions : saveVersion migration, formule ADN clamp+cap, scaling post-capstone par tranche, reset 1 gratuit/prestige + vision build-sharing, Convergence évolutif (Alpha→Omega, nœud unique à tiers) |

docs/SPRINT3.md

@@ -0,0 +1,315 @@
+# SPRINT3.md — Prestige Loop
+
+> Brief technique — Sprint 3
+> Date : 2026-03-28
+> Réf GDD : docs/GDD.md
+> Dépend : Sprint 2 livré (3/3)
+> Agents : game-designer (design) → build (implémentation)
+
+---
+
+## Objectif
+
+Transformer le prestige d'une mécanique de reset en une **boucle de progression motivante et endless**. Le joueur doit sentir l'accélération à chaque génération, faire des choix de build durables, et viser des paliers qui récompensent la spécialisation.
+
+---
+
+## Pré-requis technique — Migration saves
+
+> À traiter en amont de Step 1 — pas un step visible, mais bloquant.
+
+### Pattern `saveVersion` + `migrateSave()` (décision session 2026-03-28)
+
+Le GameState est stocké en JSON unique dans MySQL. Ajouter/modifier des champs
+sans migration = `undefined` silencieux → NaN → bugs fantômes.
+
+**Mécanisme :**
+- Ajouter `saveVersion: number` au `GameState`
+  - Saves Sprint 2 existantes = version absente → traitées comme `v1`
+  - Sprint 3 = `v2`
+- Fonction `migrateSave(state: unknown): GameState` appliquée au chargement
+  (frontend `useSaveSync` + backend `saveControllers`)
+  - `v1 → v2` : injecter defaults (`runStats` vide, `treeResetCount: 0`,
+    `freeResetAvailable: true`, `repeatableNodes: {}`, nouveaux nœuds arbre)
+  - Les 18 nœuds Sprint 2 conservent leur `id` — les nouveaux s'ajoutent
+  - Champ critique manquant → log warning + default safe (jamais de crash)
+- Chaque sprint futur ajoute un step de migration (`v2 → v3`, etc.)
+
+### Schéma DB
+
+- `ALTER TABLE game_saves ADD COLUMN save_version INT DEFAULT 1`
+- Pas de migration du JSON existant en DB — la migration est lazy (au chargement)
+
+### Validation
+
+- Charger une save Sprint 2 brute sur le nouveau code → `migrateSave` injecte v2
+- Pas de perte de données, pas de reset forcé
+- Les nœuds arbre existants (18) gardent leur position et état unlocked
+
+---
+
+## Steps
+
+### Step 1 — Prestige Experience
+
+**Scope :** Rendre le moment du prestige satisfaisant et informatif.
+
+**Design :**
+- Écran de prestige redesigné :
+  - Preview ADN gagné (avant de confirmer)
+  - Comparaison : "Run actuelle vs meilleure run" (durée, têtards, ADN)
+  - Compteur de générations (nombre total de prestiges)
+- Statistiques de run persistées :
+  - Durée de la run
+  - Têtards produits (lifetime cette run)
+  - Vitesse de progression vs run précédente (% plus rapide / plus lent)
+  - Branche d'arbre principale utilisée
+- Animation de reset : transition visuelle (le marais "renaît")
+- Hooks audio-ready : prévoir les points d'ancrage pour le son (Sprint futur)
+
+**Technique :**
+- `PrestigeScreen.tsx` : composant modal fullscreen (pas un simple bouton)
+- `RunStats` dans le GameState :
+  ```ts
+  interface RunStats {
+    startedAt: number;
+    tadpolesProduced: number;
+    prestigeCount: number;
+    bestRun: {
+      duration: number;
+      tadpoles: number;
+      adn: number;
+    };
+  }
+  ```
+- Backend : persister `runStats` dans la save (même pattern save serveur)
+- Rebalancer la formule prestige pour l'endless (voir section Formules)
+
+**Critère done :** le joueur clique Prestige → voit un écran avec preview ADN + stats comparées → confirme → animation → nouvelle run. Les stats de la meilleure run sont persistées.
+
+---
+
+### Step 2 — Arbre d'Évolution V2 — Profondeur endless
+
+**Scope :** Étendre l'arbre à ~30 nœuds avec capstones game-changers et scaling post-capstone infini.
+
+**Design — Structure par branche :**
+
+**Branche Ponte (click) — 8-10 nœuds :**
+- Tier 1 : Ponte Améliorée (+100% click) — 1 ADN
+- Tier 2 : Click Critique (5% chance ×10) — 5 ADN
+- Tier 3 : Frénésie (click power +1% par click dans les 10 dernières sec, cap +50%) — 15 ADN
+- Tier 3 alt (exclusif) : Concentration (+200% click, -25% idle) — 15 ADN
+- Capstone : **Ponte Automatique** — auto-click 1/sec, scale avec upgrades ponte — 200 ADN
+- Post-capstone (repeatable) : +5% auto-click speed, coût ×2 — départ 500 ADN
+
+**Branche Marais (production) — 8-10 nœuds :**
+- Tier 1 : Instinct Grégaire (+50% production tous générateurs) — 3 ADN
+- Tier 2 : Spécialisation (un générateur au choix ×3) — 8 ADN
+- Tier 3 : Écosystème (+10% prod par type de générateur possédé) — 25 ADN
+- Tier 3 alt (exclusif) : Monoculture (un seul type ×5, les autres ×0.5) — 25 ADN
+- Capstone : **Symbiose Totale** — chaque générateur booste les autres (+2% par type possédé) — 300 ADN
+- Post-capstone (repeatable) : +1% symbiose, coût ×2 — départ 600 ADN
+
+**Branche Adaptation (utility) — 8-10 nœuds :**
+- Tier 1 : Mémoire Génétique (commence chaque run avec 100 têtards) — 2 ADN
+- Tier 2 : Métabolisme Rapide (+25% offline cap) — 10 ADN
+- Tier 3 : Héritage (conserve 5% des générateurs tier 1 entre prestiges) — 30 ADN
+- Tier 3 alt (exclusif) : Mutation ADN (+25% ADN gagné au prestige) — 30 ADN
+- Capstone : **Mémoire du Marais** — offline cap 25% → 75%, durée 2h → 8h — 250 ADN
+- Post-capstone (repeatable) : +2% offline cap (au-delà de 75%), coût ×2 — départ 500 ADN
+
+**Nœud cross-branche — Convergence (évolutif, décision session 2026-03-28) :**
+
+Un seul nœud qui évolue quand le joueur atteint de nouveaux paliers de diversification.
+Pattern `tier` sur le nœud — fondation pour d'autres nœuds évolutifs futurs.
+
+```
+Convergence Alpha (tier 1)
+  Condition : 1 capstone + tier 3 d'une 2e branche (~prestige 12-15)
+  Coût : 500 ADN
+  Effet : +10% à tous les effets de l'arbre
+
+Convergence Omega (tier 2 — même nœud, upgrade auto)
+  Condition : 2 capstones atteintes
+  Coût : 500 ADN supplémentaires (total investi : 1000)
+  Effet : +10% tous effets + -20% coût post-capstones
+```
+
+Technique — champ `tier` sur `EvolutionNode` :
+```ts
+tier?: number;              // 1 = Alpha, 2 = Omega (current level)
+maxTier?: number;           // 2
+tierUpgradeCost?: number;   // 500
+tierUpgradeCondition?: string; // "2_capstones"
+```
+
+UX : notification "Convergence a évolué !" quand la condition tier 2 est remplie.
+Le joueur voit sa récompense grandir — pas un 2e nœud à acheter séparément.
+
+**Technique :**
+- `DEFAULT_EVOLUTION_TREE` : ~30 nœuds (tree data structure, pas array)
+- Ajouter `tier: number` et `repeatable: boolean` aux `EvolutionNode`
+- `repeatableCount: number` dans le state pour les nœuds post-capstone
+- UI : garder le layout 3 colonnes, ajouter scroll vertical par branche
+- Capstones visuellement distincts (bordure dorée, icône spéciale)
+- Cross-branche : section basse, verrouillée visuellement jusqu'aux conditions
+- Convergence : badge évolutif (Alpha → Omega), indicateur de progression vers le prochain tier
+
+**Reset arbre — 1 gratuit par prestige (décision session 2026-03-28) :**
+
+Chaque prestige offre 1 reset gratuit (nouvelle génération = nouvelle chance de build).
+Resets supplémentaires dans la même génération = payants.
+
+```
+freeResetAvailable: boolean  // true après chaque prestige, false après usage
+resetCostInGeneration: number = 5 × extraResetsUsed  // linéaire, pas exponentiel
+```
+
+| Reset# (dans la même génération) | Coût ADN |
+|----------------------------------|----------|
+| 1er | Gratuit (offert par prestige) |
+| 2e  | 5 |
+| 3e  | 10 |
+| 4e  | 15 |
+
+Pas punitif, encourage l'expérimentation, mais décourage le spam.
+
+**Fondation build-sharing (Sprint 4+ vision) :**
+Le build de l'arbre est exportable en string compacte (nœuds unlocked encodés).
+Permet le partage de builds entre joueurs et les "runs prestige" communautaires.
+→ Structurer l'arbre state pour faciliter l'export dès Sprint 3 :
+  `buildCode: string` = nœuds unlocked encodés base36 ou similaire.
+
+**Critère done :** l'arbre affiche ~30 nœuds sur 3 branches + cross-branche, les capstones changent le gameplay de manière perceptible, les post-capstones sont achetables en boucle.
+
+---
+
+### Step 3 — Milestones de Prestige
+
+**Scope :** Récompenser la persévérance avec des paliers de prestige qui débloquent cosmétiques exclusifs et bonus légers.
+
+**Design :**
+
+| Palier | Récompense | Type |
+|--------|------------|------|
+| 1 prestige | Badge "Première Génération" + ruban queue | cosmétique |
+| 3 prestiges | Titre "Gardien Récurrent" | cosmétique |
+| 5 prestiges | Start avec 1 Nid gratuit | gameplay léger |
+| 10 prestiges | Skin "Têtard Ancestral" (body prestige) + couronne dorée | cosmétique |
+| 15 prestiges | +5% offline cap permanent | gameplay léger |
+| 25 prestiges | Cape d'algues ancestrales + aura prestige | cosmétique |
+| 50 prestiges | Titre "Légende du Marais" + particules dorées permanentes | cosmétique |
+| 100 prestiges | Skin "Têtard Primordial" (full set) | cosmétique |
+
+- Les bonus gameplay sont **légers** — jamais assez pour casser l'économie
+- Les cosmétiques prestige-only ne sont pas obtenables autrement (exclusivité = motivation)
+- Écran milestones accessible depuis le menu prestige (progress bar vers le prochain palier)
+
+**Technique :**
+- `PrestigeMilestone` type :
+  ```ts
+  interface PrestigeMilestone {
+    id: string;
+    threshold: number;        // nombre de prestiges requis
+    reward: MilestoneReward;
+    claimed: boolean;
+  }
+
+  type MilestoneReward =
+    | { type: "cosmetic"; cosmeticId: string }
+    | { type: "bonus"; effect: EffectType; value: number }
+    | { type: "title"; title: string };
+  ```
+- Intégrer avec le système cosmétiques V1 existant — ajouter `source: "prestige_milestone"` aux cosmétiques
+- UI : `MilestonesPanel.tsx` — liste verticale avec progress bar, claim button, preview reward
+- Backend : valider les claims (le joueur ne peut pas claim un milestone sans le nombre de prestiges)
+
+**Critère done :** atteindre 5 prestiges → notification milestone → claim → Nid gratuit actif + cosmétique dans l'inventaire.
+
+---
+
+## Formules — Rebalancing endless (décisions session 2026-03-28)
+
+### Formule ADN (remplace l'actuelle)
+
+Actuelle : `adn = floor(150 × sqrt(lifetime_tadpoles / 1e9))` — s'aplatit trop vite.
+
+Nouvelle :
+```
+adn = max(1, floor(base × log10(tadpoles / threshold) × (1 + bonus)))
+
+  base      = 50
+  threshold = 1e6 (1M têtards — seuil minimum pour prestige)
+  bonus     = min(0.05 × prestigeCount, 3.0)  // cap ×4 max à 80 prestiges
+  clamp     = minimum 1 ADN si tadpoles >= threshold
+```
+
+| Run | Tadpoles | Prestige# | Bonus | ADN gagné |
+|-----|----------|-----------|-------|-----------|
+| 1   | 1M (seuil) | 0      | ×1.0  | **1** (clamp) |
+| 1   | 10M      | 0        | ×1.0  | **50** |
+| 5   | 100M     | 4        | ×1.20 | **120** |
+| 15  | 1B       | 14       | ×1.70 | **255** |
+| 30  | 10B      | 29       | ×2.45 | **430** |
+| 80+ | 100B     | 80       | ×4.00 | **800** (cap bonus atteint) |
+
+La courbe log scale bien : récompense toujours plus, oblige à aller exponentiellement plus loin.
+Le cap du bonus évite que l'endgame trivialise l'arbre.
+
+### Courbe coût post-capstones — paliers par tranche
+
+Le ×2 brut crée un mur après ~8 achats. Scaling par tranche :
+
+```
+Achats 1-5   : cost = base × 1.5^n
+Achats 6-10  : cost = base × 1.5^5 × 1.8^(n-5)
+Achats 11+   : cost = base × 1.5^5 × 1.8^5 × 2.0^(n-10)
+```
+
+| Achat# | Coût (base 500) | ~Runs nécessaires (400 ADN/run) |
+|--------|-----------------|--------------------------------|
+| 1      | 750             | ~2 |
+| 5      | 3 797           | ~10 |
+| 10     | 68 890          | ~172 |
+| 15     | 2.2M            | endgame long |
+
+Chaque achat reste "quelques sessions" en mid-game, puis ralentit en endgame
+sans frapper un mur infranchissable.
+
+### Courbe coût nœuds standards
+
+Définis manuellement par nœud (1, 3, 5, 8, 10, 15, 25, 30, 200, 250, 300, 500, 1000 ADN).
+
+### Vérification d'équilibre
+
+- Premier capstone : entre le 8e et 12e prestige (spécialisation une branche)
+- Arbre "complet" (hors post-capstone) : ~15-20 prestiges
+- Post-capstones : progression infinie, chaque achat = investissement plus lourd mais gain marginal
+- Cross-branche : joueur dédié à 25+ prestiges
+
+**Niveau de confiance : moyen** — les chiffres sont calibrés sur les formules mais devront être playtestés. Toutes les constantes centralisées dans `balance.ts` pour ajustement rapide.
+
+---
+
+## Résumé séquentiel
+
+```
+Migration saves → Step 1 (prestige experience) → Step 2 (arbre V2 endless) → Step 3 (milestones)
+```
+
+Step 1 = le moment. Step 2 = la profondeur. Step 3 = la motivation long terme.
+
+---
+
+## Risques identifiés
+
+| Risque | Mitigation | Statut |
+|--------|------------|--------|
+| Formule ADN mal calibrée | Constantes dans `balance.ts`. Clamp min 1 + cap bonus ×4. Playtest après Step 1 | ✅ adressé |
+| Capstones trop puissants (Ponte Auto trivialise) | Tester chaque capstone isolément. Auto-click = 1/sec de base | à tester |
+| Post-capstone wall en late-game | Scaling par tranche (×1.5/×1.8/×2.0) au lieu de ×2 brut | ✅ adressé |
+| Migration saves casse les joueurs existants | Pattern `saveVersion` + `migrateSave()` lazy. Saves Sprint 2 = v1, migrées automatiquement | ✅ adressé |
+| Reset arbre frustrant | 1 gratuit par prestige + linéaire au-delà. Pas d'exponentiel | ✅ adressé |
+| Arbre V2 complexe visuellement | Progressive disclosure : griser les nœuds non débloquables, tooltip clair | à tester |
+| Build-sharing string : encodage fragile | Valider le décodage côté client. Nœud inconnu dans le code = ignoré (forward compat) | Sprint 4 |