Combat damage

Bannerlord v1.5.7 · checked 2026-11-12 · updated 2026-11-13

How one blow becomes the damage an agent takes, and every skill, perk, banner and figurehead that changes it, at full precision for game v1.5.7.

Module overrides:

• NavalStrikeMagnitudeModel (NavalDLC) delegates every strike magnitude method to SandboxStrikeMagnitudeModel (SandBox), so the SandBox methods are live. It extends CalculateAdjustedArmorForBlow: it calls the SandBox method and then recomputes the armor from scratch (see Adjusted armor).
• NavalAgentApplyDamageModel (NavalDLC) delegates most methods to SandboxAgentApplyDamageModel (SandBox). It extends ApplyDamageAmplifications, ApplyDamageReductions, CalculateSailFireDamage, DecideMissileWeaponFlags and ShouldMissilePassThroughAfterShieldBreak, and its CalculateRemainingMomentum overwrites the base result for two-handed swings.
• NavalDLC registers both NavalStrikeMagnitudeModel and NavalAgentApplyDamageModel (extends) in sandbox and story campaigns, with no naval-battle gate. Terms not marked "naval battle" apply in every mission.
• The combat difficulty multiplier comes from SandboxMissionDifficultyModel, registered in SandBox.SandBoxSubModule::InitializeGameStarter.

Skill guides with these perks: One Handed, Two Handed, Polearm, Bow, Crossbow, Throwing, Riding, Athletics, Crafting, Tactics, Roguery, Engineering, Mariner, Shipmaster, Boatswain.

Verdicts: works = does what the tooltip says, or more — broader effects are noted; differs = narrower, different or extra conditions/values than the tooltip; unused = never read by the game; ui_only = only shown in the interface. "Captain" halves come from the captain of the agent's formation; "Personal" halves from the agent's own character.

The damage pipeline

blow_damage is the final damage of a blow to an agent. It is produced in Mission::GetAttackCollisionResults. Base raw_damage, combine rule custom, floor 0. The steps run in this order.

1. Magnitude

magnitude = source magnitude · momentum_remaining · arm_hit_multiplier · agent_weapon_damage_multiplier · weapon_damage_factor
blow_magnitude = clamp(magnitude, 0, 500)

• Source magnitude, by blow kind:
  • missile: missile_magnitude (see Missile magnitude), times momentum_remaining and agent_weapon_damage_multiplier only.
  • melee swing: the maximum of swing_strike_magnitude over 5 impact points.
  • melee thrust: thrust_strike_magnitude.
  • passive usage (couch or brace): passive_attack_damage.
  • kick or shield bash: alternative_attack_magnitude · momentum_remaining, no further terms.
  • no weapon: unarmed_magnitude, no further terms.
  • horse charge: horse_charge_magnitude.
  • fall: fall_magnitude.
• momentum_remaining: 1 for the first target, then the remaining momentum after each cleave (see Cleave momentum).
• arm_hit_multiplier: for a hit with another bone, ThrustHitWithArmDamageMultiplier (ManagedParameters 20) for thrusts and SwingHitWithArmDamageMultiplier (19) for swings; else, for a thrust that is not a tip hit and not shield-blocked, NonTipThrustHitDamageMultiplier (21); else 1.
• agent_weapon_damage_multiplier: agentstat game number.
• weapon_damage_factor: the weapon's ThrustDamageFactor for thrusts, SwingDamageFactor otherwise. Applied to weapon melee blows only, not to missiles, kicks or unarmed hits.
• The clamp to [0, 500] is applied in ComputeBlowMagnitude.

2. Armor

armor = blow_adjusted_armor + 10 (back shield hit)

• blow_adjusted_armor: the victim's armor of the hit body part after the attacker's penetration effects (see Adjusted armor). 0 for fall damage.
• +10 when the blow hits a shield the victim carries on the back (CollidedWithShieldOnBack and ShieldOnBack set).

3. Raw damage

d          = blow_magnitude · 50 / (50 + armor)
raw_damage = (b · d + (1 − b) · max(0, d − k · armor)) · absorbed_ratio

• absorbed_ratio: the victim's Monster.AbsorbedDamageRatio.
• Kick or bash, fall, horse charge, empty weapon or another-bone hits count as Blunt here. This override does not reach the bone multiplier in step 4, which uses the collision's own damage type.
• An invalid damage type asserts and returns 0.
• ComputeRawDamage lives in SandboxStrikeMagnitudeModel; NavalDLC delegates.

4. Multipliers

m = bone_multiplier · sneak_attack_damage_multiplier · combat_difficulty_multiplier
m = 1 for a shield block or fall damage

• sneak_attack_damage_multiplier: agentstat game number, only when the weapon CanWeaponDealSneakAttack.
• combat_difficulty_multiplier: Mission.DamageToPlayerMultiplier when the victim (or the rider of the victim mount) is the main agent; DamageFromPlayerToFriendsMultiplier when the victim is in the main agent's battle side and the attacker is the main agent, else DamageToFriendsMultiplier; else 1.
• bone_multiplier (GetDamageMultiplierForBodyPart, NavalDLC delegates):

5. Inflicted damage clamp

inflicted = clamp(ceil(raw_damage · m), 0, 2000)

Shield blocks replace steps 2 to 5 with the shield-block branch. A missile blocked with a weapon gives 0.

6. Model modifiers

Runs only when inflicted > 0, in AgentApplyDamageModel::CalculateDamage:

if IsDamageIgnored:  result = 0
dealt   = agent_damage_dealt(inflicted)          amplifications
scaled  = dealt · damage_scaling                 scaling
taken   = agent_damage_taken(scaled)             reductions
general = taken · (1 + throwing_damage_bonus)    Throwing weapon
                · (1 + melee_damage_bonus)       melee weapon
                · (1 + damage_multiplier_bonus)  when an attacker agent exists
result  = max(0, general)

• IsDamageIgnored: see Damage ignore chance.
• Amplifications: agent_damage_dealt. Reductions: agent_damage_taken. General modifiers: General modifiers.
• damage_scaling (ApplyDamageScaling, NavalDLC delegates): 4.5 when Mission.IsSallyOutBattle and the hit destructible component's entity has a specific script component, else 1. Needs a hit destructible component, so agent hits are unaffected.
• The throwing and melee bonuses are exclusive: Throwing-skill weapons take the throwing bonus, other melee weapons the melee bonus.

7. Round

blow_damage = Round(result)        0 when inflicted ≤ 0

Mission::GetAttackCollisionResults rounds the result into InflictedDamage and logs ModifiedDamage = round(result − inflicted).

Strike magnitude

Extra linear speed

strike_extra_linear_speed is the attacker's speed bonus that enters the swing, thrust and passive-usage magnitude formulas. Consumer SandboxStrikeMagnitudeModel::CalculateStrikeMagnitudeForSwing (SandBox); the same rule runs in CalculateStrikeMagnitudeForThrust and CalculateBaseBlowMagnitudeForPassiveUsage. Combine rule explained number, no clamp.

relative_speed     = |attacker velocity − victim velocity|
d                  = dot(weapon blow direction, normalized relative velocity)
d                  = min(d + 0.2, 1)                when d > 0
extra_linear_speed = relative_speed · d
                     · 0.7 (swing) or · 0.5 (thrust) or · 1 (passive usage)
strike_extra_linear_speed = extra_linear_speed · (1 + Σ factors)

• Velocity contributions use the mount's velocity when the agent is mounted.
• Swing and thrust add perks only when the attacker is a troop or hero and extra_linear_speed > 0; otherwise the result is extra_linear_speed. Passive usage has no such gate.
• A mounted attacker gets Nomadic Traditions only; an attacker on foot gets the on-foot perks. Lancer and Unstoppable Force apply to Polearm in both cases.
• Passive usage has no Reckless Charge or Dash and Slash terms.

Swing magnitude

swing_strike_magnitude: consumer SandboxStrikeMagnitudeModel::CalculateStrikeMagnitudeForSwing (SandBox), base swing_kinetic_magnitude, explained number, no clamp. CombatStatCalculator.CalculateStrikeMagnitudeForSwing:

r  = weapon_length · impact_point − weapon_center_of_mass
u  = swing_speed · (0.5 + weapon_center_of_mass) + strike_extra_linear_speed
E0 = 0.5 · weapon_weight · u² + 0.5 · weapon_inertia · swing_speed²
J  = (u + swing_speed · r) / (1 / weapon_weight + r² / weapon_inertia)
E1 = 0.5 · weapon_weight · (u − J / weapon_weight)² + 0.5 · weapon_inertia · (swing_speed − J · r / weapon_inertia)²
swing_kinetic_magnitude = 0.067 · (E0 − E1 + 0.5)
swing_strike_magnitude  = swing_kinetic_magnitude · (1 + Sharpened Edge)    player-crafted items only

• swing_speed = GetModifiedSwingSpeedForCurrentUsage / 4.5454545 · sqrt(speed_graph), speed_graph = SpeedGraphFunction(AttackProgress, strike type, direction).
• weapon_weight: item weight. weapon_length: GetRealWeaponLength. weapon_inertia: TotalInertia. weapon_center_of_mass: CenterOfMass.
• impact_point_i = a + i / 4 · (b − a), i = 0..4, a = min(0.93, p), b = min(0.93, p + clamp(0.4 / length, 0, 1)); the caller keeps the maximum magnitude. p = clamp(CollisionDistanceOnWeapon, −0.2, L) / L with L = length + weapon offset z.

Sharpened Edge differs: the perk is checked on the wielding agent's character, not on the smith who crafted the weapon. It applies to any player-crafted weapon, whoever wields it, if the wielder has the perk. The tooltip says crafted weapons.

Thrust magnitude

thrust_strike_magnitude: consumer SandboxStrikeMagnitudeModel::CalculateStrikeMagnitudeForThrust (SandBox), explained number, no clamp.

u = thrust_speed + strike_extra_linear_speed
thrust base = 0.0625 · (weapon_weight + 2.5) · max(u, 0)²
thrust_strike_magnitude = thrust base · (1 + Sharpened Tip)    player-crafted items only

• thrust_speed = GetModifiedThrustSpeedForCurrentUsage / 11.7647057 · sqrt(speed_graph).
• The +2.5 on the weight is skipped for thrown weapons; the melee caller passes not-thrown.

Sharpened Tip differs for the same reason as Sharpened Edge.

Worked example.

A thrust with a player-crafted 1.5 kg spear, wielded by a hero with Sharpened Tip. Inputs: weapon weight 1.5, thrust speed 7.5, strike extra linear speed 0.5.

With these inputs, melee thrust strike magnitude is 16.3200.

Passive usage magnitude

passive_attack_damage: the couch or brace blow magnitude. Consumer SandboxAgentApplyDamageModel::CalculatePassiveAttackDamage (SandBox), base passive_magnitude, sequential, no clamp.

s  = strike_extra_linear_speed
w' = weapon_weight + 20 / (s^0.1 if s > 0 else 1)
passive_magnitude = 0.0625 · (w' + 2.5) · (0.83 · s)²       0 when < 10
passive_attack_damage = passive_magnitude · (1 + Unstoppable Force)

• Computed only when the attacker or victim has a mount or the victim is a mount, else 0.
• Then blow pipeline step 1 (momentum, arm hit, weapon multiplier, damage factor).

• Unstoppable Force differs: the +3.0 factor gives four times the damage, not the tooltip's triple.

Missile magnitude

missile_speed_bonus_factor: consumer SandboxStrikeMagnitudeModel::CalculateStrikeMagnitudeForMissile (SandBox), base 0, explained number, no clamp.

v  = |victim velocity − missile velocity|   (|missile velocity| without a victim agent)
v0 = MissileStartingBaseSpeed
v' = v + (v − v0) · missile_speed_bonus_factor     when v > v0, else v' = v
missile_magnitude = (v' / v0)² · MissileTotalDamage

Running Throw differs: the tooltip shows +0.3% damage, but the game adds 25% of the missile's speed above its starting speed, which enters damage squared.

Adjusted armor

blow_adjusted_armor: the victim's armor of the hit body part after the attacker's penetration effects. Consumer NavalStrikeMagnitudeModel::CalculateAdjustedArmorForBlow (NavalDLC), base armor, combine rule custom, floor 0.

• armor = the victim's base armor effectiveness for the hit body part, the agentstat agent_armor_* value of that body part; 0 without a victim agent.
• Fall damage skips the call (armor 0).

Base model (SandBox)

a0 = armor                                       armor ≤ 0 or attacker not a troop or hero
a0 = 0                                           Piercer or Slinging Competitions applies
E  = armor · (1 + Σ SandBox factors)
a0 = max(0, armor − (E − armor))
a0 = a0 · (1 − armor_penetration_bow)            Bow weapons
a0 = a0 · (1 − armor_penetration_crossbow)       Crossbow weapons

Live model (NavalDLC recompute)

a0 = SandBox result
result = a0                                      a0 ≤ 0 or attacker not a troop or hero
E'     = armor · (1 + Σ naval factors)           fresh modifier sum from the raw armor
result = max(0, armor − (E' − armor))

• The naval model calls the base and keeps a0 only as a > 0 gate. It re-tests Piercer and Slinging Competitions (never true here: they already gave a0 = 0) and recomputes from scratch with Vandal, Chink in the Armor, Bodkin, Puncture, Weak Spot, Shattering Blow (melee) or Shattering Volley (consumable with a relevant skill).
• Each perk counts once. The SandBox factors are computed but their result is discarded whenever it is > 0; the live value comes from the naval recompute alone (plus the Piercer and Slinging Competitions zero results).
• The recompute drops the (1 − armor_penetration_bow/crossbow) step. These agent properties are raised only by the Saber-tooth tiger figurehead, so that figurehead is inert: its armor penetration never reaches damage.
• The armor perk bonuses (Vandal, Chink in the Armor, Bodkin, Puncture, Weak Spot, Shattering Blow, Shattering Volley) are positive factors summed into E = armor · (1 + Σ bonus), so the adjusted armor is max(0, armor · (1 − Σ bonus)): a +25% perk removes 25% of the hit body part's armor.
• Captain halves use the attacker's captain, nulled when it is the attacker.

• Every row except Shattering Blow, Shattering Volley and the figurehead is read by both the SandBox method and the NavalDLC recompute with the same bonus; the live value is the NavalDLC one.
• Chink in the Armor differs: only weapons with relevant skill One Handed; the tooltip says melee attacks (two-handed and polearm are not covered).
• Vandal applies before any weapon test, so every attack counts.
• Shattering Blow and Shattering Volley have no naval-battle test of their own; their halves are naval_only, so they give nothing outside naval battles, as the tooltip shows (Sea only).
• Saber-tooth tiger figurehead differs: inert, see above.

Amplifications (agent_damage_dealt)

agent_damage_dealt: blow damage after attacker amplifications. Consumer NavalAgentApplyDamageModel::ApplyDamageAmplifications (NavalDLC), base incoming_damage (the inflicted damage from step 5, only when > 0), combine rule custom, no clamp.

agent_damage_dealt = (incoming_damage + Σ S adds) · (1 + Σ S factors) · (1 + Σ N factors)

• S: terms added in SandboxAgentApplyDamageModel::ApplyDamageAmplifications. All S terms need the attacker character (the rider's character when the attacker is a mount) to be a troop or hero, else the result is incoming_damage.
• N: terms added in NavalAgentApplyDamageModel::ApplyDamageAmplifications, a standard modifier sum on the SandBox result. Terms only with an attacker that is a troop or hero.
• The two modifier sums stack multiplicatively. Factors inside one sum add.
• Shield-block damage passes through this step too (see Shield-block branch), so "damage to shields" perks act on it.

Banners (S)

Personality trait (S)

Decreased Charge Damage differs: the in-game description reuses the Increased Charge Damage text (charge damage to mounted troops in your formation). The code reduces horse-charge damage taken by any victim in the banner formation, mounted or not, and only when the charging rider is a troop or hero.

SandBox perks (S)

skill is the perk holder's skill in the perk's skill. The Way Of The Saddle uses the rider's effective Riding; 250 is MaxSkillRequiredForEpicPerkBonus.

differs reasons:

• Wood Chopper, Shield breaker and Beast Slayer secondary: applied only when the attacking troop wields a two-handed melee weapon; the tooltip says any troops in the formation.
• Last Hit: only thrown-weapon hits, which the tooltip does not state. The test is victim health ≤ 0.5 · max health, health before the blow, equality included.
• Splinters primary: a +300% percentage factor is added to the summed factors, i.e. 4× base damage on its own (more with other factors), not triple.
• Strong Legs primary: the kick bonus is a literal +100% percentage factor; no perk bonus value is read. It matches the tooltip's +100% kick damage, but it takes no environment, so it stays +100% at sea although the half is reduced at sea. Its -0.5 bonus is the fall damage reduction (see Reductions).
• Berserker and Confidence are exclusive (else-branch).

NavalDLC perks (N)

• Every Mariner half here is naval_only: the naval-battle test matches the tooltip line (Sea only), so it is not a difference. Brute Force has no naval-battle test of its own; its attacker environment gives nothing outside naval battles.
• Axe of the North Wind differs: melee axes only (thrown axes excluded); not in the tooltip.
• Sunny Disposition: daggers excluded.
• Warrior's Might primary: unarmed blows excluded.
• The Sky's Fury primary: shield hits included.
• Seaborne Fortress is a victim reduction placed in the amplification method: it reads the victim's captain.

Reductions (agent_damage_taken)

agent_damage_taken: blow damage after victim reductions. Consumer NavalAgentApplyDamageModel::ApplyDamageReductions (NavalDLC), base scaled_damage, combine rule custom, no clamp.

scaled_damage      = agent_damage_dealt · damage_scaling
agent_damage_taken = scaled_damage · (1 + Σ S factors) · (1 + Σ N factors)

• S: terms added in SandboxAgentApplyDamageModel::ApplyDamageReductions. All victim terms only when the victim character (the rider's character for a mount) is a troop or hero. Mounted Weapon Damage Penalty is an attacker term.
• N: terms added in NavalAgentApplyDamageModel::ApplyDamageReductions, a standard modifier sum on the SandBox result. Terms only with a victim that is a troop or hero and an attacker weapon.

SandBox (S)

Mounted Weapon Damage Penalty factor = min(0, −0.2 + 0.002 · Riding)

• Riding: the attacker (rider) effective Riding.
• Mounted Weapon Damage Penalty differs: skipped when the weapon's relevant skill is Crossbow, which the description does not say.
• Decreased Taken Ranged Attack Damage differs: the in-game description is the morale-shock text ("% morale penalty from casualties"); the code reduces ranged damage taken.
• Counter Fire secondary differs: only troops wielding a crossbow in the main hand get the reduction; the tooltip says all troops.
• Basher secondary differs: only melee hits are reduced; the tooltip says all damage. There is no infantry or on-foot check, so it is broader than the tooltip on that side.

NavalDLC (N)

• The helm object carries a UserDamageCalculateComponent, added to the pilot standing point. The main agent at the helm always gets the component's -0.6 factor regardless of the perk.

General modifiers

After reductions, in ApplyGeneralDamageModifiers (SandBox, NavalDLC delegates):

Shield-block branch

When the blow is blocked with a shield, ComputeBlowDamageOnShield replaces steps 2 to 5:

0 unless the shield CanBlockRanged and CanGiveDamageToAgentShield
raw    = ComputeRawDamage(damage type, magnitude, shield armor, 1)
raw    = raw · type factor
raw    = raw · 2                                   BonusAgainstShield
raw    = raw · ShieldRightStanceBlockDamageMultiplier (54)    unless the victim is in left stance   (raw > 0)
raw    = raw · ShieldCorrectSideBlockDamageMultiplier (55)    correct-side block                     (raw > 0)
shield = truncated(CalculateShieldDamage(raw))

• Shield armor: GetModifiedArmorForCurrentUsage of the shield.
• Type factor: missiles ThrowingAxe ×0.3, Javelin ×0.5, CanPenetrateShield+MultiplePenetration ×0.5, else ×0.15; melee Cut or Blunt ×0.7, Pierce ×0.5.
• CalculateShieldDamage (SandBox, NavalDLC delegates): shield · (1 + banner bonus).
• The result is stored as both inflicted damage and armor-absorbed damage.
• Step 6 still runs on this shield damage, so shield terms of the amplifications and reductions act on it: Wall Breaker, Prestige, Wood Chopper, Shield breaker, Shield Breaker (Throwing and Mariner), Splinters, Steel Core Shields, Shieldwall.

Passive attacks against shields

Unstoppable Force (Polearm) primary adds a +3.0 factor to passive_attack_damage (four times the damage) when the blow is blocked with a shield (see Passive usage magnitude).

Damage ignore chance

damage_ignore_chance: the chance that a missile hit on a back shield is ignored. Consumer SandboxAgentApplyDamageModel::IsDamageIgnored (SandBox, NavalDLC delegates), base 0, combine rule custom, no clamp.

chance  = bonus                      when a perk applies (Pavise), else 0
ignored = random roll ≤ chance       CalculateDamage returns 0

Stagger

stagger_threshold_damage: the damage needed to interrupt the victim's attack. Consumer SandboxAgentApplyDamageModel::CalculateStaggerThresholdDamage (SandBox), base damage_interrupt_threshold, explained number, no clamp. Caller MissionCombatMechanicsHelper::DecideAgentShrugOffBlow.

stagger_threshold_damage = damage_interrupt_threshold · (1 + Σ factors)

• damage_interrupt_threshold: ManagedParameters DamageInterruptAttackThresholdCut (10) for Cut, …Pierce (9) for Pierce, …Blunt (11) otherwise, by the blow's damage type.
• Perk terms only for a troop or hero agent. Mounted agents get Dauntless Steed, others Spartan (if/else). Deft Hands when the wielded crossbow is reloading.
• Captain: the formation captain's character, nulled when it is the agent.

Dismount, knockback, knockdown

Can dismount

can_weapon_dismount: boolean (1 = true). Consumer SandboxAgentApplyDamageModel::CanWeaponDismount (SandBox), custom. Caller MissionCombatMechanicsHelper::DecideAgentDismountedByBlow.

1. false unless the victim body part is in 0..6.
2. true for a swing with CanHook by an unmounted attacker, or a thrust with CanDismount.
3. else the perk overrides (troop or hero attacker).
4. else false.

Hammer Bolts and Knock Off differs: this check reads the perk without an environment, so it does not switch the land-only halves off in a naval battle. Ship crews always spawn unmounted; the Blocked Estuary story mission (a naval battle) spawns a horse for the player.

Dismount penetration

dismount_penetration: consumer SandboxAgentApplyDamageModel::GetDismountPenetration (SandBox), base 0, sequential, floor 0. Used after can_weapon_dismount.

dismount_penetration = max(0, 0 + 0.25 (swing with CanHook) + one perk add by weapon skill)

Worked example. All terms are adds, so their order does not change the sum.

A swing with a polearm that has the CanHook flag, by a hero with Braced.

With these inputs, dismount penetration is 0.5000.

Knockback penetration

knockback_penetration: consumer SandboxAgentApplyDamageModel::GetKnockBackPenetration (SandBox), base 0, sequential, no clamp. Used by MissionCombatMechanicsHelper::DecideAgentKnockedBackByBlow.

Knockdown penetration

knockdown_penetration: consumer SandboxAgentApplyDamageModel::GetKnockDownPenetration (SandBox), base 0, sequential, no clamp. Used by MissionCombatMechanicsHelper::DecideWeaponKnockDown after CanWeaponKnockDown.

1. Boulder or BallistaBoulder weapons: return 0.25 at once.
2. Non-melee weapons: 0.
3. Swing: +0.1 for a leg hit, then Show of Strength for two-handed weapons.
4. Any strike: +0.15 for a head hit, then Hard Knock for polearms.

Braced, Keep at Bay, Show of Strength, Hard Knock, Hammer Bolts and Knock Off primary are differs: their halves are Add increments, so the tooltip prints the bonus unscaled as "+0.3%" or "+0.5%" (0.25 rounds to 0.3; see Tooltip rendering), while the game subtracts 0.25, 0.3 or 0.5 from a resistance that is a 0–1 fraction of the victim's health limit (25, 30 or 50 percentage points).

Couched lance pass-through

couched_lance_pass_through_chance: the chance that a couched lance passes through after a kill. Consumer SandboxAgentApplyDamageModel::DecidePassiveAttackCollisionReaction (SandBox, NavalDLC delegates), base 0.05, sequential, no clamp.

chance = 0.05 + Skewer                       victim killed and attacker HasMount
reaction = pass through when a random roll < chance, else bounce

The caller also requires a thrust, an attacker doing a passive attack and inflicted damage > 0.

Stun after a defended blow

attacker_stun_period: consumer SandboxAgentApplyDamageModel::CalculateDefendedBlowStunMultipliers (SandBox), base attacker_stun_base, sequential, cap stun_period_max.

attacker_stun_period = min(StunPeriodMax, attacker_stun_base · max(0, 1 + Σ perk terms))     Blocked or Parried

• attacker_stun_base: computed in MissionCombatMechanicsHelper::GetDefendCollisionResults from ManagedParameters stun terms (weapon weight offsets and bonuses, stance, block kind); not decomposed.
• StunPeriodMax: ManagedParameters 46. After the model call, GetDefendCollisionResults takes min(StunPeriodMax, value).
• The defender multiplier stays 1.

Mighty Blow differs: the tooltip says enemies are stunned longer; the IL lengthens the stun period named for the attacker, i.e. the perk holder. The engine code that uses that period is native.

Cleave momentum

cleave_momentum_loss: two-handed cleave momentum loss. Consumer NavalAgentApplyDamageModel::CalculateRemainingMomentum (NavalDLC), base 0, explained number, floor 0.

cleave_momentum_loss = (0 + armor_absorbed_share) · (1 + Mighty Blows)
armor_absorbed_share = AbsorbedByArmor / InflictedDamage          when InflictedDamage > 0
remaining momentum   = (momentum − cleave_momentum_loss) · 0.5,   0 when < 0.25

• Computed only for agent hits that are not horse charges, an attacker not doing a passive attack, not a hit with another bone, a non-empty weapon, not a thrust, relevant skill Two Handed. No naval-battle gate.
• It overwrites the base result for every qualifying two-handed swing, with or without the perk.

Base rule (AgentApplyDamageModel::CalculateDefaultRemainingMomentum, used for every other blow):

crush-through                                      0.3 · momentum
needs InflictedDamage > 0, no shield block or back-shield hit, agent hit, not horse charge:
passive attack                                     0.5 · momentum
CanHitMultipleTargets (not thrust, not another bone)   momentum · (1 − armor_absorbed_share) · 0.5,   0 when < 0.25
else                                               0

The naval recompute has no crush-through, shield-block or CanHitMultipleTargets test, and subtracts the loss from momentum instead of scaling momentum.

Worked example.

A two-handed swing whose first hit had 40% of the blow absorbed by armor, by a hero with Mighty Blows. Inputs: armor absorbed share 0.4.

With these inputs, two-handed cleave momentum loss is 0.2000.

Missile flags and shield break

Missile weapon flags

missile_weapon_flags: a flag set, not a number. Consumer NavalAgentApplyDamageModel::DecideMissileWeaponFlags (NavalDLC, extends), custom.

missile_flags = missile_flags | CanPenetrateShield        when a perk applies (Impale, Crew of Spears)

Crew of Spears: naval battles only, which matches its naval_only half (Sea only). Its bonus (0.0) is not read.

Missile pass-through after a shield break

missile_pass_through_after_shield_break: boolean (1 = true). Consumer NavalAgentApplyDamageModel::ShouldMissilePassThroughAfterShieldBreak (NavalDLC, extends), base 0 (the SandBox model returns false), custom.

Crew of Spears: naval battles only, which matches its naval_only half (Sea only).

Sail fire damage

sail_fire_damage: fire damage to a ship sail. Consumer NavalAgentApplyDamageModel::CalculateSailFireDamage (NavalDLC, extends), base weapon_fire_damage, explained number, no clamp.

sail_fire_damage = (weapon_fire_damage + Σ adds) · (1 + Σ factors)

• The SandBox base model returns its damage argument unchanged.
• weapon_fire_damage: the weapon's fire damage, scaled for missiles by the missile velocity length over a reference speed (MissionShip::OnHit). The reference speed comes from native engine code.
• Captain perks come from the attacker's formation captain, self not excluded.

• Special Arrows primary differs: it also adds +5 flat sail fire damage, not stated by the tooltip. MissionShip::OnHit marks the hit as coming from a siege engine, so only the sail-hit path applies. The add was intended for the secondary half.
• Special Arrows secondary unused: the only sail-damage reader applies the primary half (role Captain, +5 add) and never the secondary FirstMate +40% factor.
• The Sea Serpent factor also applies to hull fire damage, which no skill touches.

Game code

Decoded IL of the methods above (game v1.5.7):

• TaleWorlds.MountAndBlade.Mission.il: GetAttackCollisionResults (final rounding).
• TaleWorlds.MountAndBlade.MissionCombatMechanicsHelper.il: ComputeBlowMagnitude, ComputeBlowMagnitudeMelee, ComputeBlowMagnitudeMissile, ComputeBlowMagnitudeFromHorseCharge, ComputeBlowMagnitudeFromFall, CalculateBaseMeleeBlowMagnitude, ConvertBaseAttackMagnitude, ComputeBlowDamage, ComputeBlowDamageOnShield, GetDefendCollisionResults.
• TaleWorlds.MountAndBlade.ComponentInterfaces.AgentApplyDamageModel.il: CalculateDamage, CalculateDefaultRemainingMomentum.
• TaleWorlds.MountAndBlade.AttackInformation.il: armor, absorbed ratio, bone multiplier and captain fields.
• TaleWorlds.Core.CombatStatCalculator.il: swing, thrust and passive-usage magnitude formulas.
• SandBox.GameComponents.SandboxStrikeMagnitudeModel.il: CalculateStrikeMagnitudeForSwing, CalculateStrikeMagnitudeForThrust, CalculateBaseBlowMagnitudeForPassiveUsage, CalculateStrikeMagnitudeForMissile, CalculateStrikeMagnitudeForUnarmedAttack, CalculateAdjustedArmorForBlow, ComputeRawDamage.
• NavalDLC.GameComponents.NavalStrikeMagnitudeModel.il: CalculateAdjustedArmorForBlow (recompute).
• SandBox.GameComponents.SandboxAgentApplyDamageModel.il: ApplyDamageAmplifications, ApplyDamageScaling, ApplyDamageReductions, ApplyGeneralDamageModifiers, CalculateShieldDamage, CalculateAlternativeAttackDamage, CalculatePassiveAttackDamage, GetDamageMultiplierForBodyPart, IsDamageIgnored, CalculateStaggerThresholdDamage, CanWeaponDismount, GetDismountPenetration, GetKnockBackPenetration, GetKnockDownPenetration, DecidePassiveAttackCollisionReaction, CalculateDefendedBlowStunMultipliers, DecideMissileWeaponFlags.
• NavalDLC.GameComponents.NavalAgentApplyDamageModel.il: ApplyDamageAmplifications, ApplyDamageReductions, CalculateRemainingMomentum, CalculateSailFireDamage, DecideMissileWeaponFlags, ShouldMissilePassThroughAfterShieldBreak.
• SandBox.GameComponents.SandboxMissionDifficultyModel.il: GetDamageMultiplierOfCombatDifficulty.

Changelog

• v1.5.7 (2026-11-12): Re-verified against v1.5.7 IL: Calculating trait charge-damage factor added; Unstoppable Force adds a +300% factor (×4); Pavise is no longer clamped; Skewer adds 0.25; Accuracy Training applies; perk halves follow the perk effect environment; Braced, Keep at Bay, Show of Strength, Hard Knock, Hammer Bolts and Knock Off dismount/knockdown halves are differs (tooltip +0.3% or +0.5%).
• v1.4.8 (2026-11-11): First version from IL.