Code Changes (Run A → Run B)

Index: simulator/src/testcases.test.ts
===================================================================
--- simulator/src/testcases.test.ts	prev run
+++ simulator/src/testcases.test.ts	this run
@@ -284,8 +284,27 @@
 
   assert.deepEqual(input.mechanics, { weather: "clear", engagement_type: "rally" });
 });
 
+test("adaptTestcaseEntry merges option mechanics without replacing testcase mechanics", () => {
+  const input = adaptTestcaseEntry(
+    {
+      test_id: "mechanics_case",
+      engagement_type: "rally",
+      mechanics: { weather: "clear" },
+      attacker: { troops: { infantry_t1: 1 } },
+      defender: { troops: { infantry_t1: 1 } }
+    },
+    { mechanics: { carryAttackDurationEffectsToTriggeredExtraSkillDamage: true } }
+  );
+
+  assert.deepEqual(input.mechanics, {
+    weather: "clear",
+    carryAttackDurationEffectsToTriggeredExtraSkillDamage: true,
+    engagement_type: "rally"
+  });
+});
+
 test("compareOutcomeDistribution matches deterministic zero-bias shape", () => {
   const metrics = compareOutcomeDistribution({
     candidate: { n: 1, mu: -186, sigma: 0 },
     reference: { n: 1, mu: -186, sigma: 0 },
Index: simulator/src/testcases.ts
===================================================================
--- simulator/src/testcases.ts	prev run
+++ simulator/src/testcases.ts	this run
@@ -26,8 +26,9 @@
   repeat?: number;
   seed?: string | number;
   trace?: boolean;
   workers?: number;
+  mechanics?: Record<string, unknown>;
 }
 
 export interface TestcaseCaseReport {
   file: string;
@@ -206,9 +207,9 @@
       const diagnostics: string[] = [];
       const detail = emptyCaseReport(reportFile, testcaseId, index, diagnostics);
       const preparedCase: PreparedTestcaseCase = { file, reportFile, entry, testcaseId, index, detail };
       try {
-        preparedCase.input = adaptTestcaseEntry(entry, { seed: options.seed, trace: options.trace }, diagnostics);
+        preparedCase.input = adaptTestcaseEntry(entry, { seed: options.seed, trace: options.trace, mechanics: options.mechanics }, diagnostics);
         preparedCase.key = snapshotKey(reportFile, index);
       } catch (error) {
         detail.error = errorMessage(error);
         diagnostics.push(detail.error);
@@ -612,9 +613,13 @@
   const { details: _details, ...summary } = report;
   return summary;
 }
 
-export function adaptTestcaseEntry(entry: unknown, options: { seed?: string | number; trace?: boolean } = {}, diagnostics: string[] = []): BattleInput {
+export function adaptTestcaseEntry(
+  entry: unknown,
+  options: { seed?: string | number; trace?: boolean; mechanics?: Record<string, unknown> } = {},
+  diagnostics: string[] = []
+): BattleInput {
   const object = entry as {
     attacker?: FighterInput;
     defender?: FighterInput;
     test_id?: string;
@@ -625,9 +630,9 @@
     max_rounds?: unknown;
   };
   if (!object.attacker || !object.defender) throw new Error(`Testcase ${object.test_id ?? "(unknown)"} is missing attacker or defender`);
   diagnostics.push(...diagnoseFighterShape("attacker", object.attacker), ...diagnoseFighterShape("defender", object.defender));
-  const mechanics = testcaseMechanics(object);
+  const mechanics = testcaseMechanics(object, options.mechanics);
   const maxRounds = optionalNumber(object.maxRounds ?? object.max_rounds);
   return {
     attacker: object.attacker,
     defender: object.defender,
@@ -701,10 +706,14 @@
   if (!fighter.stats) diagnostics.push(`${side} has no stats block`);
   return diagnostics;
 }
 
-function testcaseMechanics(entry: { mechanics?: Record<string, unknown>; engagement_type?: unknown; engagementType?: unknown }): Record<string, unknown> | undefined {
+function testcaseMechanics(
+  entry: { mechanics?: Record<string, unknown>; engagement_type?: unknown; engagementType?: unknown },
+  optionMechanics?: Record<string, unknown>
+): Record<string, unknown> | undefined {
   const mechanics = entry.mechanics && typeof entry.mechanics === "object" ? { ...entry.mechanics } : {};
+  if (optionMechanics && typeof optionMechanics === "object") Object.assign(mechanics, optionMechanics);
   if (entry.engagement_type !== undefined) mechanics.engagement_type = entry.engagement_type;
   if (entry.engagementType !== undefined) mechanics.engagementType = entry.engagementType;
   return Object.keys(mechanics).length > 0 ? mechanics : undefined;
 }

diff --git a/simulator/src/damage.ts b/simulator/src/damage.ts
--- a/simulator/src/damage.ts
+++ b/simulator/src/damage.ts
@@ -38,6 +38,7 @@
   effect: ActiveEffect;
   bucket: AtomicBucket;
   valuePct: number;
+  carriedInactive?: boolean;
 }
 
 interface MaxBucketCandidateGroup {
@@ -123,13 +124,17 @@
   const consumedEffectIds = new Set<string>();
   const candidates: BucketCandidate[] = [];
   const handledCandidateEffectIds = traceEnabled ? new Set<string>() : undefined;
+  const carriedAttackDurationEffectIds = job.carriedAttackDurationEffectIds ? new Set(job.carriedAttackDurationEffectIds) : undefined;
   for (const candidate of bucketCandidatesForJob(options.effectIndex, job)) {
-    if (!isEffectActive(candidate.effect, job.round)) continue;
+    const active = isEffectActive(candidate.effect, job.round);
+    const carriedInactive = !active && carriedAttackDurationEffectIds?.has(candidate.effect.id) === true;
+    if (!active && !carriedInactive) continue;
     handledCandidateEffectIds?.add(candidate.effect.id);
     candidates.push({
       effect: candidate.effect,
       bucket: candidate.bucket,
-      valuePct: currentEffectValuePct(candidate.effect, job.round)
+      valuePct: currentEffectValuePct(candidate.effect, job.round),
+      carriedInactive
     });
   }
 
@@ -267,7 +272,7 @@
       appliedEffects.push(appliedEffect);
     }
     for (const candidate of candidates) {
-      if (candidate.effect.duration.type === "attack") consumedEffectIds.add(candidate.effect.id);
+      if (candidate.effect.duration.type === "attack" && !candidate.carriedInactive) 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/simulator/src/simulator.test.ts b/simulator/src/simulator.test.ts
--- a/simulator/src/simulator.test.ts
+++ b/simulator/src/simulator.test.ts
@@ -1323,6 +1323,87 @@
   assert.deepEqual(result.extraSkillAttackJobsByEffect, { hitLiving: 4 });
 });
 
+test("attack-duration normal damage effects do not carry to triggered extra skill damage by default", () => {
+  const result = simulateBattle(
+    {
+      maxRounds: 1,
+      trace: true,
+      attacker: {
+        troops: { marksman_t1: 100 },
+        heroes: { FollowUp: { skill_1: 1, skill_2: 1 } }
+      },
+      defender: {
+        troops: { infantry_t1: 100 },
+        heroes: {}
+      }
+    },
+    attackDurationCarryConfig()
+  );
+
+  const normalBoosts = result.attacks
+    .filter((attack) => attack.kind === "normal" && attack.attackerSide === "attacker")
+    .map((attack) => attack.trace?.atomicBuckets["active.hero.attack.up"].totalPct ?? 0);
+  const skillBoosts = result.attacks
+    .filter((attack) => attack.kind === "skill")
+    .map((attack) => attack.trace?.atomicBuckets["active.hero.attack.up"].totalPct ?? 0);
+  assert.deepEqual(normalBoosts, [100]);
+  assert.deepEqual(skillBoosts, [0]);
+});
+
+test("mechanics flag carries consumed attack-duration effects to matching triggered extra skill damage only", () => {
+  const result = simulateBattle(
+    {
+      maxRounds: 1,
+      trace: true,
+      mechanics: { carryAttackDurationEffectsToTriggeredExtraSkillDamage: true },
+      attacker: {
+        troops: { marksman_t1: 100 },
+        heroes: { FollowUp: { skill_1: 1, skill_2: 1 } }
+      },
+      defender: {
+        troops: { infantry_t1: 100, lancer_t1: 100, marksman_t1: 100 },
+        heroes: {}
+      }
+    },
+    attackDurationCarryConfig({ buffAppliesVs: "infantry", extraTargets: "enemy.living" })
+  );
+
+  const normalBoosts = result.attacks
+    .filter((attack) => attack.kind === "normal" && attack.attackerSide === "attacker")
+    .map((attack) => attack.trace?.atomicBuckets["active.hero.attack.up"].totalPct ?? 0);
+  const skillBoostsByTarget = result.attacks
+    .filter((attack) => attack.kind === "skill")
+    .map((attack) => `${attack.defenderUnit}:${attack.trace?.atomicBuckets["active.hero.attack.up"].totalPct ?? 0}`)
+    .sort();
+  assert.deepEqual(normalBoosts, [100]);
+  assert.deepEqual(skillBoostsByTarget, ["infantry:100", "lancer:0", "marksman:0"]);
+});
+
+test("mechanics flag carries consumed attack-duration effects with any target scope to all matching triggered extra skill damage", () => {
+  const result = simulateBattle(
+    {
+      maxRounds: 1,
+      trace: true,
+      mechanics: { carryAttackDurationEffectsToTriggeredExtraSkillDamage: true },
+      attacker: {
+        troops: { marksman_t1: 100 },
+        heroes: { FollowUp: { skill_1: 1, skill_2: 1 } }
+      },
+      defender: {
+        troops: { infantry_t1: 100, lancer_t1: 100, marksman_t1: 100 },
+        heroes: {}
+      }
+    },
+    attackDurationCarryConfig({ buffAppliesVs: "any", extraTargets: "enemy.living" })
+  );
+
+  const skillBoosts = result.attacks
+    .filter((attack) => attack.kind === "skill")
+    .map((attack) => attack.trace?.atomicBuckets["active.hero.attack.up"].totalPct ?? 0)
+    .sort((left, right) => left - right);
+  assert.deepEqual(skillBoosts, [100, 100, 100]);
+});
+
 test("attack-triggered source and target selectors resolve to concrete active scopes", () => {
   const result = simulateBattle(
     {
@@ -1801,3 +1882,40 @@
     diagnostics: { legacyFields: [], effectTypes: {}, unsupportedEffects: [], ambiguousTurnTriggerSelectors: [] }
   };
 }
+
+function attackDurationCarryConfig(
+  options: { buffAppliesVs?: "any" | "infantry"; extraTargets?: "use.target" | "enemy.living" } = {}
+): SimulatorConfig {
+  const buffAppliesVs = options.buffAppliesVs ?? "any";
+  const extraTargets = options.extraTargets ?? "use.target";
+  return minimalConfig({
+    FollowUp: {
+      name: "FollowUp",
+      skills: {
+        OneUseNormalBoost: {
+          trigger: { type: "battle_start" },
+          effects: {
+            boost: {
+              type: "active.hero.attack.up",
+              value: 100,
+              units: { applies_to: "marksman", applies_vs: buffAppliesVs },
+              duration: { type: "attack", value: 1 }
+            }
+          }
+        },
+        TriggeredExtraDamage: {
+          trigger: { type: "attack", probability: 100, source: "marksman" },
+          effects: {
+            extra: {
+              type: "extra_skill_attack",
+              value: 100,
+              units: { applies_to: "trigger.source", applies_vs: "any" },
+              trigger_damage_jobs: [{ source: "use.source", target: extraTargets }],
+              duration: { type: "attack", value: 1 }
+            }
+          }
+        }
+      }
+    }
+  });
+}
diff --git a/simulator/src/simulator.ts b/simulator/src/simulator.ts
--- a/simulator/src/simulator.ts
+++ b/simulator/src/simulator.ts
@@ -53,6 +53,7 @@
   extraSkillAttackJobsByEffect: Record<string, number>;
   attackControlCounts: { dodge: number; no_attack: number };
   consumedEffectUseKeys: Set<string>;
+  carryAttackDurationEffectsToTriggeredExtraSkillDamage: boolean;
   counters: {
     attacks: Record<SideId, Record<UnitType, number>>;
     received: Record<SideId, Record<UnitType, number>>;
@@ -112,7 +113,7 @@
   const attacker = resolveFighter(input.attacker, "attacker", config, input.mechanics);
   const defender = resolveFighter(input.defender, "defender", config, input.mechanics);
   const fighters: Record<SideId, ResolvedFighter> = { attacker, defender };
-  const runtime = createRuntime([attacker, defender], createSeededRng(input.seed ?? "simulator-default"));
+  const runtime = createRuntime([attacker, defender], createSeededRng(input.seed ?? "simulator-default"), input.mechanics);
   const detail = options.detail ?? "full";
   const traceEnabled = detail === "full" && input.trace;
   const trace: BattleTrace | undefined = traceEnabled ? { resolved: buildResolved(attacker, defender), rounds: [] } : undefined;
@@ -289,7 +290,7 @@
   return Number.isFinite(value) && value > 0 && value < 100;
 }
 
-function createRuntime(fighters: ResolvedFighter[], rng: Rng): Runtime {
+function createRuntime(fighters: ResolvedFighter[], rng: Rng, mechanics?: BattleInput["mechanics"]): Runtime {
   const reports: Record<SideId, Map<string, SkillReportEntry>> = { attacker: new Map(), defender: new Map() };
   const skills = buildRuntimeSkills(fighters);
   for (const fighter of fighters) {
@@ -321,6 +322,7 @@
     extraSkillAttackJobsByEffect: {},
     attackControlCounts: { dodge: 0, no_attack: 0 },
     consumedEffectUseKeys: new Set(),
+    carryAttackDurationEffectsToTriggeredExtraSkillDamage: mechanics?.carryAttackDurationEffectsToTriggeredExtraSkillDamage === true,
     counters: {
       attacks: { attacker: emptyTroops(), defender: emptyTroops() },
       received: { attacker: emptyTroops(), defender: emptyTroops() }
@@ -513,6 +515,9 @@
   roundStartTroops: DamageJob["roundStartTroops"]
 ): DamageJob[] {
   const jobs: DamageJob[] = [];
+  const carriedAttackDurationEffectIds = runtime.carryAttackDurationEffectsToTriggeredExtraSkillDamage
+    ? attackDurationBucketEffectIdsForJob(normalAttack, round, runtime.activeEffects)
+    : undefined;
   const effectGroups = selectStackedExtraAttackEffectGroups(
     runtime.effectIndex.extraAttacks.filter((effect) => isEffectActive(effect, round) && extraAttackEffectAppliesToNormalAttack(effect, normalAttack)),
     round
@@ -548,6 +553,7 @@
             sourceEffectId,
             sourceSkillReportKey,
             sourceMultiplier: multiplier,
+            carriedAttackDurationEffectIds,
             consumedEffectIds,
             consumedEffectUseKey,
             consumedEffectUseId: effect.id,
@@ -745,6 +751,16 @@
     .map((effect) => effect.id);
 }
 
+function attackDurationBucketEffectIdsForJob(job: DamageJob, round: number, effects: ActiveEffect[]): string[] {
+  return effects
+    .filter((effect) => {
+      if (effect.kind === "extra_attack" || effect.duration.type !== "attack" || !isEffectActive(effect, round)) return false;
+      const classification = classifyEffectForJob(effect, job);
+      return classification?.kind === "bucket";
+    })
+    .map((effect) => effect.id);
+}
+
 function consumeEffects(
   runtime: Runtime,
   consumedEffectIds: string[],
diff --git a/simulator/src/types.ts b/simulator/src/types.ts
--- a/simulator/src/types.ts
+++ b/simulator/src/types.ts
@@ -277,6 +277,7 @@
   sourceEffectId?: string;
   sourceSkillReportKey?: string;
   sourceMultiplier?: number;
+  carriedAttackDurationEffectIds?: string[];
   consumedEffectIds?: string[];
   consumedEffectUseKey?: string;
   consumedEffectUseId?: string;

diff --git a/simulator/src/damage.ts b/simulator/src/damage.ts
--- a/simulator/src/damage.ts
+++ b/simulator/src/damage.ts
@@ -38,6 +38,7 @@
   effect: ActiveEffect;
   bucket: AtomicBucket;
   valuePct: number;
+  carriedInactive?: boolean;
 }
 
 interface MaxBucketCandidateGroup {
@@ -123,13 +124,17 @@
   const consumedEffectIds = new Set<string>();
   const candidates: BucketCandidate[] = [];
   const handledCandidateEffectIds = traceEnabled ? new Set<string>() : undefined;
+  const carriedAttackDurationEffectIds = job.carriedAttackDurationEffectIds ? new Set(job.carriedAttackDurationEffectIds) : undefined;
   for (const candidate of bucketCandidatesForJob(options.effectIndex, job)) {
-    if (!isEffectActive(candidate.effect, job.round)) continue;
+    const active = isEffectActive(candidate.effect, job.round);
+    const carriedInactive = !active && carriedAttackDurationEffectIds?.has(candidate.effect.id) === true;
+    if (!active && !carriedInactive) continue;
     handledCandidateEffectIds?.add(candidate.effect.id);
     candidates.push({
       effect: candidate.effect,
       bucket: candidate.bucket,
-      valuePct: currentEffectValuePct(candidate.effect, job.round)
+      valuePct: currentEffectValuePct(candidate.effect, job.round),
+      carriedInactive
     });
   }
 
@@ -267,7 +272,7 @@
       appliedEffects.push(appliedEffect);
     }
     for (const candidate of candidates) {
-      if (candidate.effect.duration.type === "attack") consumedEffectIds.add(candidate.effect.id);
+      if (candidate.effect.duration.type === "attack" && !candidate.carriedInactive) 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/simulator/src/simulator.test.ts b/simulator/src/simulator.test.ts
--- a/simulator/src/simulator.test.ts
+++ b/simulator/src/simulator.test.ts
@@ -1323,6 +1323,87 @@
   assert.deepEqual(result.extraSkillAttackJobsByEffect, { hitLiving: 4 });
 });
 
+test("attack-duration normal damage effects do not carry to triggered extra skill damage by default", () => {
+  const result = simulateBattle(
+    {
+      maxRounds: 1,
+      trace: true,
+      attacker: {
+        troops: { marksman_t1: 100 },
+        heroes: { FollowUp: { skill_1: 1, skill_2: 1 } }
+      },
+      defender: {
+        troops: { infantry_t1: 100 },
+        heroes: {}
+      }
+    },
+    attackDurationCarryConfig()
+  );
+
+  const normalBoosts = result.attacks
+    .filter((attack) => attack.kind === "normal" && attack.attackerSide === "attacker")
+    .map((attack) => attack.trace?.atomicBuckets["active.hero.attack.up"].totalPct ?? 0);
+  const skillBoosts = result.attacks
+    .filter((attack) => attack.kind === "skill")
+    .map((attack) => attack.trace?.atomicBuckets["active.hero.attack.up"].totalPct ?? 0);
+  assert.deepEqual(normalBoosts, [100]);
+  assert.deepEqual(skillBoosts, [0]);
+});
+
+test("mechanics flag carries consumed attack-duration effects to matching triggered extra skill damage only", () => {
+  const result = simulateBattle(
+    {
+      maxRounds: 1,
+      trace: true,
+      mechanics: { carryAttackDurationEffectsToTriggeredExtraSkillDamage: true },
+      attacker: {
+        troops: { marksman_t1: 100 },
+        heroes: { FollowUp: { skill_1: 1, skill_2: 1 } }
+      },
+      defender: {
+        troops: { infantry_t1: 100, lancer_t1: 100, marksman_t1: 100 },
+        heroes: {}
+      }
+    },
+    attackDurationCarryConfig({ buffAppliesVs: "infantry", extraTargets: "enemy.living" })
+  );
+
+  const normalBoosts = result.attacks
+    .filter((attack) => attack.kind === "normal" && attack.attackerSide === "attacker")
+    .map((attack) => attack.trace?.atomicBuckets["active.hero.attack.up"].totalPct ?? 0);
+  const skillBoostsByTarget = result.attacks
+    .filter((attack) => attack.kind === "skill")
+    .map((attack) => `${attack.defenderUnit}:${attack.trace?.atomicBuckets["active.hero.attack.up"].totalPct ?? 0}`)
+    .sort();
+  assert.deepEqual(normalBoosts, [100]);
+  assert.deepEqual(skillBoostsByTarget, ["infantry:100", "lancer:0", "marksman:0"]);
+});
+
+test("mechanics flag carries consumed attack-duration effects with any target scope to all matching triggered extra skill damage", () => {
+  const result = simulateBattle(
+    {
+      maxRounds: 1,
+      trace: true,
+      mechanics: { carryAttackDurationEffectsToTriggeredExtraSkillDamage: true },
+      attacker: {
+        troops: { marksman_t1: 100 },
+        heroes: { FollowUp: { skill_1: 1, skill_2: 1 } }
+      },
+      defender: {
+        troops: { infantry_t1: 100, lancer_t1: 100, marksman_t1: 100 },
+        heroes: {}
+      }
+    },
+    attackDurationCarryConfig({ buffAppliesVs: "any", extraTargets: "enemy.living" })
+  );
+
+  const skillBoosts = result.attacks
+    .filter((attack) => attack.kind === "skill")
+    .map((attack) => attack.trace?.atomicBuckets["active.hero.attack.up"].totalPct ?? 0)
+    .sort((left, right) => left - right);
+  assert.deepEqual(skillBoosts, [100, 100, 100]);
+});
+
 test("attack-triggered source and target selectors resolve to concrete active scopes", () => {
   const result = simulateBattle(
     {
@@ -1801,3 +1882,40 @@
     diagnostics: { legacyFields: [], effectTypes: {}, unsupportedEffects: [], ambiguousTurnTriggerSelectors: [] }
   };
 }
+
+function attackDurationCarryConfig(
+  options: { buffAppliesVs?: "any" | "infantry"; extraTargets?: "use.target" | "enemy.living" } = {}
+): SimulatorConfig {
+  const buffAppliesVs = options.buffAppliesVs ?? "any";
+  const extraTargets = options.extraTargets ?? "use.target";
+  return minimalConfig({
+    FollowUp: {
+      name: "FollowUp",
+      skills: {
+        OneUseNormalBoost: {
+          trigger: { type: "battle_start" },
+          effects: {
+            boost: {
+              type: "active.hero.attack.up",
+              value: 100,
+              units: { applies_to: "marksman", applies_vs: buffAppliesVs },
+              duration: { type: "attack", value: 1 }
+            }
+          }
+        },
+        TriggeredExtraDamage: {
+          trigger: { type: "attack", probability: 100, source: "marksman" },
+          effects: {
+            extra: {
+              type: "extra_skill_attack",
+              value: 100,
+              units: { applies_to: "trigger.source", applies_vs: "any" },
+              trigger_damage_jobs: [{ source: "use.source", target: extraTargets }],
+              duration: { type: "attack", value: 1 }
+            }
+          }
+        }
+      }
+    }
+  });
+}
diff --git a/simulator/src/simulator.ts b/simulator/src/simulator.ts
--- a/simulator/src/simulator.ts
+++ b/simulator/src/simulator.ts
@@ -53,6 +53,7 @@
   extraSkillAttackJobsByEffect: Record<string, number>;
   attackControlCounts: { dodge: number; no_attack: number };
   consumedEffectUseKeys: Set<string>;
+  carryAttackDurationEffectsToTriggeredExtraSkillDamage: boolean;
   counters: {
     attacks: Record<SideId, Record<UnitType, number>>;
     received: Record<SideId, Record<UnitType, number>>;
@@ -112,7 +113,7 @@
   const attacker = resolveFighter(input.attacker, "attacker", config, input.mechanics);
   const defender = resolveFighter(input.defender, "defender", config, input.mechanics);
   const fighters: Record<SideId, ResolvedFighter> = { attacker, defender };
-  const runtime = createRuntime([attacker, defender], createSeededRng(input.seed ?? "simulator-default"));
+  const runtime = createRuntime([attacker, defender], createSeededRng(input.seed ?? "simulator-default"), input.mechanics);
   const detail = options.detail ?? "full";
   const traceEnabled = detail === "full" && input.trace;
   const trace: BattleTrace | undefined = traceEnabled ? { resolved: buildResolved(attacker, defender), rounds: [] } : undefined;
@@ -289,7 +290,7 @@
   return Number.isFinite(value) && value > 0 && value < 100;
 }
 
-function createRuntime(fighters: ResolvedFighter[], rng: Rng): Runtime {
+function createRuntime(fighters: ResolvedFighter[], rng: Rng, mechanics?: BattleInput["mechanics"]): Runtime {
   const reports: Record<SideId, Map<string, SkillReportEntry>> = { attacker: new Map(), defender: new Map() };
   const skills = buildRuntimeSkills(fighters);
   for (const fighter of fighters) {
@@ -321,6 +322,7 @@
     extraSkillAttackJobsByEffect: {},
     attackControlCounts: { dodge: 0, no_attack: 0 },
     consumedEffectUseKeys: new Set(),
+    carryAttackDurationEffectsToTriggeredExtraSkillDamage: mechanics?.carryAttackDurationEffectsToTriggeredExtraSkillDamage === true,
     counters: {
       attacks: { attacker: emptyTroops(), defender: emptyTroops() },
       received: { attacker: emptyTroops(), defender: emptyTroops() }
@@ -513,6 +515,9 @@
   roundStartTroops: DamageJob["roundStartTroops"]
 ): DamageJob[] {
   const jobs: DamageJob[] = [];
+  const carriedAttackDurationEffectIds = runtime.carryAttackDurationEffectsToTriggeredExtraSkillDamage
+    ? attackDurationBucketEffectIdsForJob(normalAttack, round, runtime.activeEffects)
+    : undefined;
   const effectGroups = selectStackedExtraAttackEffectGroups(
     runtime.effectIndex.extraAttacks.filter((effect) => isEffectActive(effect, round) && extraAttackEffectAppliesToNormalAttack(effect, normalAttack)),
     round
@@ -548,6 +553,7 @@
             sourceEffectId,
             sourceSkillReportKey,
             sourceMultiplier: multiplier,
+            carriedAttackDurationEffectIds,
             consumedEffectIds,
             consumedEffectUseKey,
             consumedEffectUseId: effect.id,
@@ -745,6 +751,16 @@
     .map((effect) => effect.id);
 }
 
+function attackDurationBucketEffectIdsForJob(job: DamageJob, round: number, effects: ActiveEffect[]): string[] {
+  return effects
+    .filter((effect) => {
+      if (effect.kind === "extra_attack" || effect.duration.type !== "attack" || !isEffectActive(effect, round)) return false;
+      const classification = classifyEffectForJob(effect, job);
+      return classification?.kind === "bucket";
+    })
+    .map((effect) => effect.id);
+}
+
 function consumeEffects(
   runtime: Runtime,
   consumedEffectIds: string[],
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
@@ -285,6 +285,25 @@
   assert.deepEqual(input.mechanics, { weather: "clear", engagement_type: "rally" });
 });
 
+test("adaptTestcaseEntry merges option mechanics without replacing testcase mechanics", () => {
+  const input = adaptTestcaseEntry(
+    {
+      test_id: "mechanics_case",
+      engagement_type: "rally",
+      mechanics: { weather: "clear" },
+      attacker: { troops: { infantry_t1: 1 } },
+      defender: { troops: { infantry_t1: 1 } }
+    },
+    { mechanics: { carryAttackDurationEffectsToTriggeredExtraSkillDamage: true } }
+  );
+
+  assert.deepEqual(input.mechanics, {
+    weather: "clear",
+    carryAttackDurationEffectsToTriggeredExtraSkillDamage: true,
+    engagement_type: "rally"
+  });
+});
+
 test("compareOutcomeDistribution matches deterministic zero-bias shape", () => {
   const metrics = compareOutcomeDistribution({
     candidate: { n: 1, mu: -186, sigma: 0 },
diff --git a/simulator/src/testcases.ts b/simulator/src/testcases.ts
--- a/simulator/src/testcases.ts
+++ b/simulator/src/testcases.ts
@@ -27,6 +27,7 @@
   seed?: string | number;
   trace?: boolean;
   workers?: number;
+  mechanics?: Record<string, unknown>;
 }
 
 export interface TestcaseCaseReport {
@@ -207,7 +208,7 @@
       const detail = emptyCaseReport(reportFile, testcaseId, index, diagnostics);
       const preparedCase: PreparedTestcaseCase = { file, reportFile, entry, testcaseId, index, detail };
       try {
-        preparedCase.input = adaptTestcaseEntry(entry, { seed: options.seed, trace: options.trace }, diagnostics);
+        preparedCase.input = adaptTestcaseEntry(entry, { seed: options.seed, trace: options.trace, mechanics: options.mechanics }, diagnostics);
         preparedCase.key = snapshotKey(reportFile, index);
       } catch (error) {
         detail.error = errorMessage(error);
@@ -613,7 +614,11 @@
   return summary;
 }
 
-export function adaptTestcaseEntry(entry: unknown, options: { seed?: string | number; trace?: boolean } = {}, diagnostics: string[] = []): BattleInput {
+export function adaptTestcaseEntry(
+  entry: unknown,
+  options: { seed?: string | number; trace?: boolean; mechanics?: Record<string, unknown> } = {},
+  diagnostics: string[] = []
+): BattleInput {
   const object = entry as {
     attacker?: FighterInput;
     defender?: FighterInput;
@@ -626,7 +631,7 @@
   };
   if (!object.attacker || !object.defender) throw new Error(`Testcase ${object.test_id ?? "(unknown)"} is missing attacker or defender`);
   diagnostics.push(...diagnoseFighterShape("attacker", object.attacker), ...diagnoseFighterShape("defender", object.defender));
-  const mechanics = testcaseMechanics(object);
+  const mechanics = testcaseMechanics(object, options.mechanics);
   const maxRounds = optionalNumber(object.maxRounds ?? object.max_rounds);
   return {
     attacker: object.attacker,
@@ -702,8 +707,12 @@
   return diagnostics;
 }
 
-function testcaseMechanics(entry: { mechanics?: Record<string, unknown>; engagement_type?: unknown; engagementType?: unknown }): Record<string, unknown> | undefined {
+function testcaseMechanics(
+  entry: { mechanics?: Record<string, unknown>; engagement_type?: unknown; engagementType?: unknown },
+  optionMechanics?: Record<string, unknown>
+): Record<string, unknown> | undefined {
   const mechanics = entry.mechanics && typeof entry.mechanics === "object" ? { ...entry.mechanics } : {};
+  if (optionMechanics && typeof optionMechanics === "object") Object.assign(mechanics, optionMechanics);
   if (entry.engagement_type !== undefined) mechanics.engagement_type = entry.engagement_type;
   if (entry.engagementType !== undefined) mechanics.engagementType = entry.engagementType;
   return Object.keys(mechanics).length > 0 ? mechanics : undefined;
diff --git a/simulator/src/types.ts b/simulator/src/types.ts
--- a/simulator/src/types.ts
+++ b/simulator/src/types.ts
@@ -277,6 +277,7 @@
   sourceEffectId?: string;
   sourceSkillReportKey?: string;
   sourceMultiplier?: number;
+  carriedAttackDurationEffectIds?: string[];
   consumedEffectIds?: string[];
   consumedEffectUseKey?: string;
   consumedEffectUseId?: string;