Damage Calculation

All large numbers in Darkstar use the NumberUnit encoding to handle values that exceed standard floating-point precision. A NumberUnit stores two components:

value = quotient * 10^exponent

For example, a ship with fPowerQuotient = 3.45 and iPowerExponent = 12 has a base ATK of 3.45 × 10¹² (3.45 trillion). All arithmetic in the damage pipeline operates on NumberUnit values.

BasicShipStatus

The resolved runtime stats for a ship after all modifiers are applied. Built during battle initialization from the ship's base stats plus all equipment, admiral, memory card, gemstone, and building bonuses.

BasicSkillData

The resolved skill parameters for the current attack action.

DamageInfo

The output structure produced by the damage calculation pipeline. Passed to the target for HP reduction.

The damage formula is a multi-step pipeline executed by BattleManager. Each step applies a category of modifiers. The chain proceeds in this order:

Step 1: Base Damage

BaseDamage = ATK * SkillPower

The attacker's total ATK (from BasicShipStatus) is multiplied by the skill's power coefficient. Both are NumberUnit values.

Step 2: Defense Reduction

// Physical damage:
PostDefense = BaseDamage * (1 - DEF / (DEF + ScalingConstant))

// Magical damage:
PostDefense = BaseDamage * (1 - MDEF / (MDEF + ScalingConstant))

Defense reduces damage using a diminishing-returns formula. The ScalingConstant determines how quickly defense effectiveness falls off.

Step 3: Critical Hit

if (random() < CritChance):
    PostCrit = PostDefense * CritDamage
else:
    PostCrit = PostDefense

Crit chance is checked per hit. If the skill has a non-zero SkillCritChance, it overrides the ship's base crit rate. Same for SkillCritDamage.

Step 4: Modifier Categories (28+)

After the base/defense/crit calculation, the engine applies 28+ categories of multiplicative and additive modifiers. These come from equipment, admirals, memory cards, gemstones, buildings, buffs, debuffs, and mode-specific effects.

FinalDamage =
    ATK
    * SkillPower
    * DefenseReduction(DEF_or_MDEF)
    * CritMultiplier
    * ProductOf(All Multiplicative Modifiers)
    * (1 + SumOf(All Additive Modifiers))

In practice, the formula is more nuanced because some modifier categories stack additively within their group before being multiplied with other groups. The exact behavior for each PropertyType is defined in BattleManager.CalculateDamage().

EffectiveDPS =
    FinalDamage
    * AttackSpeed
    * (1 + CritChance * (CritDamage - 1))
    * TargetCount

This gives the expected damage per second accounting for crit probability. For AoE skills with iMaxTargetCount = -1, multiply by the average number of targets present.