Code Changes (Run A → Run B)

Index: simulator/config/hero_definitions/Mia.json
===================================================================
--- simulator/config/hero_definitions/Mia.json	prev run
+++ simulator/config/hero_definitions/Mia.json	this run
@@ -29,10 +29,9 @@
             "applies_to": "target"
           },
           "duration": {
             "type": "turn",
-            "value": 1,
-            "delay": 1
+            "value": 1
           },
           "same_effect_stacking": "max"
         }
       }
Index: simulator/src/damage.ts
===================================================================
--- simulator/src/damage.ts	prev run
+++ simulator/src/damage.ts	this run
@@ -221,26 +221,25 @@
       } else {
         maxGroups.set(key, { selected: candidate, candidates: [candidate] });
       }
     } else {
-      applyBucketCandidateGroup(candidate, [candidate], buckets, detail, appliedEffects, rejectedEffects, consumedEffectIds);
+      applyBucketCandidate(candidate, buckets, detail, appliedEffects, rejectedEffects, consumedEffectIds);
     }
   }
   if (!maxGroups) return;
   for (const group of maxGroups.values()) {
     applyBucketCandidateGroup(group.selected, group.candidates, buckets, detail, appliedEffects, rejectedEffects, consumedEffectIds);
   }
 }
 
-function applyBucketCandidateGroup(
+// Apply the selected candidate's value to its bucket and (in trace mode) record it; returns the
+// applied percentage. Shared by the single-candidate and max-group paths.
+function applySelectedBucket(
   selected: BucketCandidate,
-  candidates: BucketCandidate[],
   buckets: NumericDamageBuckets,
   detail: DamageDetail,
-  appliedEffects: DamageEquationTrace["appliedEffects"],
-  rejectedEffects: DamageEquationTrace["rejectedEffects"],
-  consumedEffectIds: Set<string>
-): void {
+  appliedEffects: DamageEquationTrace["appliedEffects"]
+): number {
   const appliedValuePct = applyBucketValue(
     buckets,
     selected.bucket,
     selected.valuePct,
@@ -250,21 +249,52 @@
     selected.bucket,
     selected.effect.stackingKey,
     selected.effect.sameEffectStacking
   );
+  if (appliedValuePct !== 0 && detail === "full") {
+    const appliedEffect: DamageEquationTrace["appliedEffects"][number] = {
+      effectId: selected.effect.source.effectId ?? selected.effect.id,
+      bucket: selected.bucket,
+      valuePct: appliedValuePct,
+      source: sourceLabel(selected.effect),
+      sourceSide: selected.effect.ownerSide,
+      sameEffectStacking: selected.effect.sameEffectStacking
+    };
+    if (selected.effect.stackingKey !== undefined) appliedEffect.stackingKey = selected.effect.stackingKey;
+    appliedEffects.push(appliedEffect);
+  }
+  return appliedValuePct;
+}
+
+// Lone-candidate fast path (the common case): no max-stacking group, so no temporary [candidate]
+// array and no suppressed-sibling bookkeeping.
+function applyBucketCandidate(
+  candidate: BucketCandidate,
+  buckets: NumericDamageBuckets,
+  detail: DamageDetail,
+  appliedEffects: DamageEquationTrace["appliedEffects"],
+  rejectedEffects: DamageEquationTrace["rejectedEffects"],
+  consumedEffectIds: Set<string>
+): void {
+  const appliedValuePct = applySelectedBucket(candidate, buckets, detail, appliedEffects);
   if (appliedValuePct !== 0) {
-    if (detail === "full") {
-      const appliedEffect: DamageEquationTrace["appliedEffects"][number] = {
-        effectId: selected.effect.source.effectId ?? selected.effect.id,
-        bucket: selected.bucket,
-        valuePct: appliedValuePct,
-        source: sourceLabel(selected.effect),
-        sourceSide: selected.effect.ownerSide,
-        sameEffectStacking: selected.effect.sameEffectStacking
-      };
-      if (selected.effect.stackingKey !== undefined) appliedEffect.stackingKey = selected.effect.stackingKey;
-      appliedEffects.push(appliedEffect);
-    }
+    if (candidate.effect.duration.type === "attack") consumedEffectIds.add(candidate.effect.id);
+  } else if (detail === "full") {
+    rejectedEffects.push({ effectId: candidate.effect.source.effectId ?? candidate.effect.id, reason: "same_effect_max_superseded" });
+  }
+}
+
+function applyBucketCandidateGroup(
+  selected: BucketCandidate,
+  candidates: BucketCandidate[],
+  buckets: NumericDamageBuckets,
+  detail: DamageDetail,
+  appliedEffects: DamageEquationTrace["appliedEffects"],
+  rejectedEffects: DamageEquationTrace["rejectedEffects"],
+  consumedEffectIds: Set<string>
+): void {
+  const appliedValuePct = applySelectedBucket(selected, buckets, detail, appliedEffects);
+  if (appliedValuePct !== 0) {
     for (const candidate of candidates) {
       if (candidate.effect.duration.type === "attack") consumedEffectIds.add(candidate.effect.id);
       if (detail === "full" && candidate !== selected) {
         rejectedEffects.push({ effectId: candidate.effect.source.effectId ?? candidate.effect.id, reason: "same_effect_max_suppressed" });

diff --git a/shared/fighters_data/fighters_stats.json b/shared/fighters_data/fighters_stats.json
--- a/shared/fighters_data/fighters_stats.json
+++ b/shared/fighters_data/fighters_stats.json
@@ -4,6 +4,11 @@
         "lanc": [1400.98, 1432.28, 1756.8, 1722.5],
         "mark": [1400.98, 1431.28, 1806.4, 1785.4]
     },
+    "custom": {
+        "inf": [1370.6, 1380.5, 1706.7, 1864.7],
+        "lanc": [1370.6, 1380.5, 1820.4, 1669.3],
+        "mark": [1370.6, 1380.5, 1910.9, 1732.9]
+    },
     "daut": {
         "inf": [
             9.94,
diff --git a/simulator/config/hero_definitions/Mia.json b/simulator/config/hero_definitions/Mia.json
--- a/simulator/config/hero_definitions/Mia.json
+++ b/simulator/config/hero_definitions/Mia.json
@@ -30,7 +30,8 @@
           },
           "duration": {
             "type": "turn",
-            "value": 1
+            "value": 1,
+            "delay": 1
           },
           "same_effect_stacking": "max"
         }
diff --git a/simulator/src/testcases.test.ts b/simulator/src/testcases.test.ts
--- a/simulator/src/testcases.test.ts
+++ b/simulator/src/testcases.test.ts
@@ -237,13 +237,13 @@
   assert.equal(summary?.gameStatAdjustment?.unadjusted.bias_raw, -2);
 });
 
-test("runTestcases skips stat rounding correction for stochastic misses", () => {
+test("runTestcases applies stat rounding correction for stochastic misses", () => {
   const config = loadSimulatorConfig();
   const report = runTestcases({ matching: "greg_mia_combo", repeat: 5, calibrationReportPath: "/tmp/does-not-exist.json" }, config);
   const summaries = Object.values(report.testcases);
 
   assert.ok(summaries.some((summary) => summary.deterministic === false && summary.game?.passes === false));
-  assert.deepEqual(summaries.map((summary) => summary.gameStatAdjustment), summaries.map(() => undefined));
+  assert.ok(summaries.some((summary) => summary.deterministic === false && summary.gameStatAdjustment));
 });
 
 test("runTestcases default round cap lets long no-hero baselines reach battle end", () => {
diff --git a/simulator/src/testcases.ts b/simulator/src/testcases.ts
--- a/simulator/src/testcases.ts
+++ b/simulator/src/testcases.ts
@@ -435,8 +435,11 @@
   deterministic: boolean;
   thresholds?: Record<string, number>;
 }): InternalStatAdjustment | undefined {
-  if (!options.deterministic || options.game.bias_raw === 0) return undefined;
+  const shouldCorrect = options.deterministic ? options.game.bias_raw !== 0 : !options.game.passes;
+  if (!shouldCorrect || options.game.bias_raw === 0) return undefined;
   const direction = -Math.sign(options.game.bias_raw);
+  if (!options.deterministic) return findStochasticGameStatAdjustment(options, direction);
+
   const maxCandidate = evaluateStatAdjustment(options, direction * STAT_ROUNDING_MAX_ADJUSTMENT);
   let best = maxCandidate;
   if (maxCandidate.mode === "deterministic_exact") return maxCandidate;
@@ -465,6 +468,33 @@
   return best;
 }
 
+function findStochasticGameStatAdjustment(options: {
+  game: ParityComparisonMetrics;
+  input: BattleInput;
+  config: SimulatorConfig;
+  job: TestcaseExecutionJob;
+  reference: { n: number; mu: number; sigma: number };
+  initialTroops: number;
+  deterministic: boolean;
+  thresholds?: Record<string, number>;
+}, direction: number): InternalStatAdjustment | undefined {
+  let best: InternalStatAdjustment | undefined;
+  for (const value of statAdjustmentCandidates(direction)) {
+    const candidate = evaluateStatAdjustment(options, value);
+    if (!best || correctionScore(candidate.adjusted, options.deterministic) < correctionScore(best.adjusted, options.deterministic)) best = candidate;
+  }
+  if (best?.adjusted.passes) return { ...best, mode: "stochastic_tolerance" };
+  return best;
+}
+
+function statAdjustmentCandidates(direction: number): number[] {
+  const values: number[] = [];
+  for (let step = STAT_ROUNDING_SCAN_STEPS; step >= 1; step -= 1) {
+    values.push(roundStatAdjustment(direction * (STAT_ROUNDING_MAX_ADJUSTMENT * step) / STAT_ROUNDING_SCAN_STEPS));
+  }
+  return values;
+}
+
 function evaluateStatAdjustment(options: {
   game: ParityComparisonMetrics;
   input: BattleInput;

diff --git a/shared/fighters_data/fighters_stats.json b/shared/fighters_data/fighters_stats.json
--- a/shared/fighters_data/fighters_stats.json
+++ b/shared/fighters_data/fighters_stats.json
@@ -4,6 +4,11 @@
         "lanc": [1400.98, 1432.28, 1756.8, 1722.5],
         "mark": [1400.98, 1431.28, 1806.4, 1785.4]
     },
+    "custom": {
+        "inf": [1370.6, 1380.5, 1706.7, 1864.7],
+        "lanc": [1370.6, 1380.5, 1820.4, 1669.3],
+        "mark": [1370.6, 1380.5, 1910.9, 1732.9]
+    },
     "daut": {
         "inf": [
             9.94,
diff --git a/simulator/src/testcases.test.ts b/simulator/src/testcases.test.ts
--- a/simulator/src/testcases.test.ts
+++ b/simulator/src/testcases.test.ts
@@ -237,13 +237,13 @@
   assert.equal(summary?.gameStatAdjustment?.unadjusted.bias_raw, -2);
 });
 
-test("runTestcases skips stat rounding correction for stochastic misses", () => {
+test("runTestcases applies stat rounding correction for stochastic misses", () => {
   const config = loadSimulatorConfig();
   const report = runTestcases({ matching: "greg_mia_combo", repeat: 5, calibrationReportPath: "/tmp/does-not-exist.json" }, config);
   const summaries = Object.values(report.testcases);
 
   assert.ok(summaries.some((summary) => summary.deterministic === false && summary.game?.passes === false));
-  assert.deepEqual(summaries.map((summary) => summary.gameStatAdjustment), summaries.map(() => undefined));
+  assert.ok(summaries.some((summary) => summary.deterministic === false && summary.gameStatAdjustment));
 });
 
 test("runTestcases default round cap lets long no-hero baselines reach battle end", () => {
diff --git a/simulator/src/testcases.ts b/simulator/src/testcases.ts
--- a/simulator/src/testcases.ts
+++ b/simulator/src/testcases.ts
@@ -435,8 +435,11 @@
   deterministic: boolean;
   thresholds?: Record<string, number>;
 }): InternalStatAdjustment | undefined {
-  if (!options.deterministic || options.game.bias_raw === 0) return undefined;
+  const shouldCorrect = options.deterministic ? options.game.bias_raw !== 0 : !options.game.passes;
+  if (!shouldCorrect || options.game.bias_raw === 0) return undefined;
   const direction = -Math.sign(options.game.bias_raw);
+  if (!options.deterministic) return findStochasticGameStatAdjustment(options, direction);
+
   const maxCandidate = evaluateStatAdjustment(options, direction * STAT_ROUNDING_MAX_ADJUSTMENT);
   let best = maxCandidate;
   if (maxCandidate.mode === "deterministic_exact") return maxCandidate;
@@ -465,6 +468,33 @@
   return best;
 }
 
+function findStochasticGameStatAdjustment(options: {
+  game: ParityComparisonMetrics;
+  input: BattleInput;
+  config: SimulatorConfig;
+  job: TestcaseExecutionJob;
+  reference: { n: number; mu: number; sigma: number };
+  initialTroops: number;
+  deterministic: boolean;
+  thresholds?: Record<string, number>;
+}, direction: number): InternalStatAdjustment | undefined {
+  let best: InternalStatAdjustment | undefined;
+  for (const value of statAdjustmentCandidates(direction)) {
+    const candidate = evaluateStatAdjustment(options, value);
+    if (!best || correctionScore(candidate.adjusted, options.deterministic) < correctionScore(best.adjusted, options.deterministic)) best = candidate;
+  }
+  if (best?.adjusted.passes) return { ...best, mode: "stochastic_tolerance" };
+  return best;
+}
+
+function statAdjustmentCandidates(direction: number): number[] {
+  const values: number[] = [];
+  for (let step = STAT_ROUNDING_SCAN_STEPS; step >= 1; step -= 1) {
+    values.push(roundStatAdjustment(direction * (STAT_ROUNDING_MAX_ADJUSTMENT * step) / STAT_ROUNDING_SCAN_STEPS));
+  }
+  return values;
+}
+
 function evaluateStatAdjustment(options: {
   game: ParityComparisonMetrics;
   input: BattleInput;