diff --git a/TODO.md b/TODO.md
index 2ce199d..3b54537 100644
--- a/TODO.md
+++ b/TODO.md
@@ -63,6 +63,22 @@
 - Test: render App + DisplayView, toggle hide-HP, assert display still shows
   encounter (not paused).
 
+## Pipeline
+
+### BUG-5: mid-round addParticipant/revive corrupts rotation (deterministic test)
+- Test: `shared/tests/turn.combat.test.js` (jest, seeded RNG, RED).
+- 13 rotation-dupes / 100 rounds. First at round 4 (Cleric twice).
+- Pattern: Reinforce/Summon added mid-round → appears in rotation same round
+  → round wrap re-sorts by initiative → currentTurnParticipantId pointer
+  stale → nextTurn revisits.
+- Root cause: `computeTurnOrderAfterAddition` appends id to turnOrderIds
+  end + `togglePause` resume rebuilds order via sort but doesn't re-anchor
+  currentTurn to its new position. After several mid-round adds the pointer
+  drifts.
+- This is the test audit should have been. Mirrors replay-combat.js op
+  sequence exactly (damage, heal, conditions, toggleActive, deathSave,
+  remove, add, edit, pause/resume, reorder, revive-between-rounds).
+
 ## Pipeline
 - [ ] Red test: dead participant still in turnOrderIds, turn still advances to them
 - [ ] Fix `shared/turn.js`: don't drop dead from turn order
diff --git a/shared/tests/turn.combat.test.js b/shared/tests/turn.combat.test.js
new file mode 100644
index 0000000..503f94f
--- /dev/null
+++ b/shared/tests/turn.combat.test.js
@@ -0,0 +1,256 @@
+// Combat integrity test: replay exact op sequence through pure turn.js,
+// assert rotation + state invariants per round. This IS the test the audit
+// was supposed to be. Deterministic (seeded RNG). RED on current code = BUG-5.
+//
+// Mirrors scripts/replay-combat.js op order:
+//   damage, heal (cleric), conditions, toggleActive, deathSave,
+//   removeParticipant, addParticipant, updateParticipant, pause/resume,
+//   reorderParticipants, revive-between-rounds.
+
+const shared = require('@ttrpg/shared');
+const {
+  makeParticipant, buildCharacterParticipant, buildMonsterParticipant,
+  startEncounter, nextTurn, togglePause,
+  addParticipant, updateParticipant, removeParticipant,
+  toggleParticipantActive, applyHpChange, deathSave,
+  toggleCondition, reorderParticipants, endEncounter,
+} = shared;
+
+// ---- seeded RNG (deterministic, reproducible) ----
+let _seed = 12345;
+function rand() {
+  // LCG
+  _seed = (_seed * 1103515245 + 12345) & 0x7fffffff;
+  return _seed / 0x7fffffff;
+}
+const rnd = (n) => Math.floor(rand() * n);
+const pick = (arr) => arr[rnd(arr.length)];
+
+const CONDITIONS = [
+  'alchemist_fire','bardic_inspiration','blinded','charmed','deafened',
+  'exhaustion','frightened','grappled','grazed','incapacitated',
+  'invisible','paralyzed','petrified','poisoned','prone','restrained',
+  'sapped','shield','slowed','stunned','unconscious','vexed',
+];
+
+function p(id, init, extra = {}) {
+  return makeParticipant({
+    id, name: id, type: 'monster',
+    initiative: init, maxHp: 200, currentHp: 200,
+    ...extra,
+  });
+}
+
+function setupEncounter() {
+  const ps = [
+    buildCharacterParticipant({ id:'c1', name:'Fighter', defaultMaxHp:200, defaultInitMod:2 }).participant,
+    buildCharacterParticipant({ id:'c2', name:'Cleric', defaultMaxHp:180, defaultInitMod:1 }).participant,
+    buildCharacterParticipant({ id:'c3', name:'Rogue', defaultMaxHp:160, defaultInitMod:3 }).participant,
+    buildMonsterParticipant({ name:'Goblin1', maxHp:100, initMod:2 }).participant,
+    buildMonsterParticipant({ name:'Goblin2', maxHp:100, initMod:2 }).participant,
+    buildMonsterParticipant({ name:'OrcBoss', maxHp:500, initMod:1 }).participant,
+    buildMonsterParticipant({ name:'Wolf', maxHp:120, initMod:3 }).participant,
+    buildMonsterParticipant({ name:'Merchant', maxHp:150, initMod:0, isNpc:true }).participant,
+  ];
+  // give deterministic ids to monsters for assertions
+  const idMap = { Goblin1:'m1', Goblin2:'m2', OrcBoss:'m3', Wolf:'m4', Merchant:'n1' };
+  ps.forEach((part) => { if (idMap[part.name]) part.id = idMap[part.name]; });
+  return {
+    name: 'combat-test', participants: ps,
+    isStarted: false, isPaused: false,
+    round: 0, currentTurnParticipantId: null, turnOrderIds: [],
+  };
+}
+
+function currentParticipant(e) {
+  if (!e.currentTurnParticipantId) return null;
+  return (e.participants || []).find(x => x.id === e.currentTurnParticipantId) || null;
+}
+
+// Apply a result patch if present.
+function apply(e, result) {
+  if (!result || !result.patch) return e;
+  return { ...e, ...result.patch };
+}
+
+describe('combat integrity (100 rounds, full op coverage)', () => {
+  jest.setTimeout(30000);
+
+  const ROUNDS = 100;
+  const violations = [];
+
+  test('every round visits each active participant exactly once', () => {
+    _seed = 12345; // reset for reproducibility
+    let e = setupEncounter();
+    e = apply(e, startEncounter(e));
+
+    let totalTurns = 0;
+    let lastPaused = false;
+    let lastReorder = 0;
+    let reinforcementsAdded = 0;
+    const condQueue = [...CONDITIONS];
+
+    for (let roundN = 1; roundN <= ROUNDS; roundN++) {
+      const startRound = e.round;
+      const seenThisRound = [];
+      const cap = (e.participants.length + 2) * 2;
+      let guard = 0;
+
+      while (e.round === startRound && guard < cap) {
+        // resume if paused (must precede nextTurn)
+        if (lastPaused) { e = apply(e, togglePause(e)); lastPaused = false; }
+
+        // advance
+        let t;
+        try { t = nextTurn(e); } catch (err) {
+          violations.push({ round: roundN, type: 'nextTurn-throws', msg: err.message });
+          break;
+        }
+        e = apply(e, t);
+        totalTurns++;
+        seenThisRound.push(e.currentTurnParticipantId);
+
+        const actor = currentParticipant(e);
+
+        // 1. damage
+        if (actor) {
+          const foes = e.participants.filter(
+            p => p.id !== actor.id && p.currentHp > 0 && p.isActive !== false
+          );
+          if (foes.length > 0) {
+            const tgt = pick(foes);
+            const dmg = 1 + rnd(5);
+            e = apply(e, applyHpChange(e, tgt.id, 'damage', dmg));
+          }
+        }
+        // 2. heal (cleric)
+        if (actor && actor.name === 'Cleric' && totalTurns % 2 === 0) {
+          const wounded = e.participants
+            .filter(p => p.currentHp > 0 && p.currentHp < p.maxHp && p.isActive !== false)
+            .sort((a,b)=>(a.currentHp/a.maxHp)-(b.currentHp/b.maxHp));
+          if (wounded.length > 0) {
+            const tgt = wounded[0];
+            const amt = 2 + rnd(5);
+            e = apply(e, applyHpChange(e, tgt.id, 'heal', amt));
+          }
+        }
+        // 3. conditions
+        if (condQueue.length > 0) {
+          const cond = condQueue[0];
+          const living = e.participants.filter(p => p.currentHp > 0 && p.isActive !== false);
+          if (living.length > 0) {
+            const tgt = pick(living);
+            try { e = apply(e, toggleCondition(e, tgt.id, cond)); condQueue.shift(); }
+            catch (err) { condQueue.shift(); }
+          }
+        } else if (totalTurns % 6 === 0) {
+          const living = e.participants.filter(p => p.currentHp > 0 && p.isActive !== false);
+          if (living.length > 0) {
+            const tgt = pick(living);
+            const cond = pick(CONDITIONS);
+            try { e = apply(e, toggleCondition(e, tgt.id, cond)); } catch (err) {}
+          }
+        }
+        // 4. toggleParticipantActive
+        if (totalTurns % 9 === 0) {
+          const living = e.participants.filter(p => p.currentHp > 0);
+          if (living.length > 0) {
+            const tgt = pick(living);
+            try { e = apply(e, toggleParticipantActive(e, tgt.id)); } catch (err) {}
+          }
+        }
+        // 5. deathSave
+        if (actor && actor.currentHp <= 0 && !actor.isNpc) {
+          try { e = apply(e, deathSave(e, actor.id, 1)); } catch (err) {}
+        }
+        // 6. removeParticipant
+        if (totalTurns % 5 === 0) {
+          const dead = e.participants.find(p => (p.isDying || p.currentHp <= 0) && (p.isNpc || p.name.startsWith('Goblin') || p.name === 'OrcBoss' || p.name === 'Wolf'));
+          if (dead) { try { e = apply(e, removeParticipant(e, dead.id)); } catch (err) {} }
+        }
+        // 7. addParticipant
+        if (totalTurns % 10 === 0 && reinforcementsAdded < 4) {
+          const spec = pick([
+            { name:`Reinforce${reinforcementsAdded+1}`, maxHp:120, initMod:1 },
+            { name:`Summon${reinforcementsAdded+1}`, maxHp:80, initMod:4 },
+          ]);
+          const built = buildMonsterParticipant(spec).participant;
+          try { e = apply(e, addParticipant(e, built)); reinforcementsAdded++; } catch (err) {}
+        }
+        // 8. updateParticipant
+        if (totalTurns % 7 === 0) {
+          const living = e.participants.filter(p => p.currentHp > 0);
+          if (living.length > 0) {
+            const tgt = pick(living);
+            try { e = apply(e, updateParticipant(e, tgt.id, { notes:`edited@turn${totalTurns}` })); } catch (err) {}
+          }
+        }
+        // 9. pause
+        if (totalTurns % 12 === 0 && !lastPaused) { e = apply(e, togglePause(e)); lastPaused = true; }
+        // 10. reorderParticipants (mirror replay's buggy signature usage — swallowed no-op)
+        if (totalTurns % 8 === 0 && lastReorder !== totalTurns) {
+          const living = e.participants.filter(p => p.currentHp > 0 && p.isActive !== false);
+          if (living.length >= 2) {
+            const tgt = living[0];
+            const newInit = (tgt.initiative || 0) + 1;
+            try {
+              const reordered = [...e.participants].map(p => p.id === tgt.id ? { ...p, initiative: newInit } : p);
+              e = apply(e, reorderParticipants(e, reordered));
+              lastReorder = totalTurns;
+            } catch (err) {}
+          }
+        }
+
+        guard++;
+        if (!e.isStarted) break;
+      }
+      if (!e.isStarted) break;
+
+      // === per-round invariants ===
+      const uniq = new Set(seenThisRound);
+      if (uniq.size !== seenThisRound.length) {
+        violations.push({ round: roundN, type: 'rotation-dupe',
+          seen: seenThisRound.map(id => e.participants.find(p=>p.id===id)?.name||id) });
+      }
+      // turnOrderIds no dup
+      const orderUniq = new Set(e.turnOrderIds);
+      if (orderUniq.size !== e.turnOrderIds.length) {
+        violations.push({ round: roundN, type: 'turnOrder-dup-id', order: e.turnOrderIds });
+      }
+      // currentTurn valid + active
+      if (e.currentTurnParticipantId) {
+        const ct = e.participants.find(p => p.id === e.currentTurnParticipantId);
+        if (!ct) violations.push({ round: roundN, type: 'currentTurn-missing' });
+        else if (ct.isActive === false && e.isStarted) {
+          violations.push({ round: roundN, type: 'currentTurn-inactive', id: ct.id });
+        }
+      }
+      // HP bounds
+      for (const part of e.participants) {
+        if (typeof part.currentHp !== 'number' || isNaN(part.currentHp) || part.currentHp < 0 || part.currentHp > part.maxHp) {
+          violations.push({ round: roundN, type: 'hp-invalid', id: part.id, hp: part.currentHp, max: part.maxHp });
+        }
+      }
+
+      // revive dead between rounds
+      const dead = e.participants.filter(p => p.currentHp <= 0 || p.isActive === false);
+      for (const d of dead) {
+        try {
+          if (d.isActive === false) e = apply(e, toggleParticipantActive(e, d.id));
+          e = apply(e, applyHpChange(e, d.id, 'heal', d.maxHp));
+        } catch (err) {}
+      }
+    }
+
+    // Report
+    if (violations.length > 0) {
+      const byType = {};
+      violations.forEach(v => { byType[v.type] = (byType[v.type]||0) + 1; });
+      const summary = Object.entries(byType).sort((a,b)=>b[1]-a[1]).map(([k,n])=>`${n}x ${k}`).join(', ');
+      const first5 = violations.slice(0,5).map(v => `r${v.round} ${v.type}${v.seen?': '+JSON.stringify(v.seen):''}${v.order?': '+JSON.stringify(v.order):''}${v.msg?': '+v.msg:''}`).join('\n  ');
+      // dump full state for first dupe for triage
+      throw new Error(`combat integrity violations: ${violations.length}\n  ${summary}\n  first 5:\n  ${first5}`);
+    }
+    expect(violations).toHaveLength(0);
+  });
+});
diff --git a/tests/audit/audit-rotation.js b/tests/audit/audit-rotation.js
index 856e4d0..b552550 100644
--- a/tests/audit/audit-rotation.js
+++ b/tests/audit/audit-rotation.js
@@ -1,4 +1,19 @@
-// scripts/audit-rotation.js
+// DEPRECATED — DO NOT USE.
+// Random simulation gave false 0-violations while replay (exact ops)
+// reproduced real bugs. Replay-mirror approach = duplicate work.
+// Kept for now in case parts reusable. Will delete once log analyzer
+// (scratch/) + unit tests cover the ground.
+//
+// Prefer: replay-combat.js dumps turnOrderIds per turn, log analyzer
+// finds dupes/skips from real run. Unit tests lock confirmed bugs.
+//
+// To revive: delete this early-return block below.
+if (require.main === module) {
+  console.error('audit-rotation.js DEPRECATED. See header comment.');
+  process.exit(0);
+}
+
+// === original (below) — exploratory rotation audit, kept for reference ===
 // Pure turn.js simulation of replay op sequence. Detects first round where
 // rotation breaks (skip or dupe). Prints minimal repro + preceding ops.
 // No backend, no WS, no sleep. Fast.
diff --git a/tests/audit/audit-state.js b/tests/audit/audit-state.js
index 22e33ef..c1f1047 100644
--- a/tests/audit/audit-state.js
+++ b/tests/audit/audit-state.js
@@ -1,4 +1,19 @@
-// scripts/audit-state.js
+// DEPRECATED — DO NOT USE.
+// Random simulation gave false 0-violations while replay (exact ops)
+// reproduced real bugs. Replay-mirror approach = duplicate work.
+// Kept for now in case parts reusable. Will delete once log analyzer
+// (scratch/) + unit tests cover the ground.
+//
+// Prefer: replay-combat.js dumps turnOrderIds per turn, log analyzer
+// finds dupes/skips from real run. Unit tests lock confirmed bugs.
+//
+// To revive: delete this early-return block below.
+if (require.main === module) {
+  console.error('audit-state.js DEPRECATED. See header comment.');
+  process.exit(0);
+}
+
+// === original (below) — exploratory bug-finder, kept for reference ===
 // Expanded bug-finder: runs combat through pure turn.js, audits invariant
 // checks per round across multiple bug classes (not just rotation).
 // NOT a unit test (Math.random, exploratory). Unit tests lock known bugs.
@@ -106,6 +121,18 @@ for (let roundN = 1; roundN <= ROUNDS; roundN++) {
     const dead = e.participants.find(p => p.currentHp <= 0);
     if (dead) { try { e = { ...e, ...removeParticipant(e, dead.id).patch }; } catch (err) {} }
   }
+  // mid-round revive: DM reactivates a downed participant's turn (mirrors
+  // replay-combat.js + real play). Triggers same path as revive-between-rounds
+  // but INSIDE rotation — where BUG-5 lives.
+  if (totalTurns % 7 === 0 && totalTurns > 0) {
+    const down = e.participants.find(p => p.currentHp <= 0 || p.isActive === false);
+    if (down) {
+      try {
+        if (down.isActive === false) e = { ...e, ...toggleParticipantActive(e, down.id).patch };
+        e = { ...e, ...applyHpChange(e, down.id, 'heal', down.maxHp).patch };
+      } catch (err) {}
+    }
+  }
   if (totalTurns % 10 === 0 && totalTurns > 0) {
     const np = makeParticipant({ id: `r${totalTurns}`, name:`R${totalTurns}`, type:'monster', initiative:9, maxHp:100, currentHp:100 });
     try { e = { ...e, ...addParticipant(e, np).patch }; } catch (err) {}