Pokémon Black Version and Pokémon White Version - Damage Calculation

Tags: pokemon-black-and-white, battle-system, in-depth-guides, damage

Power is modified by these effects in this order:

1. Effects of most attacks that vary their power do so at this point. Examples include Acrobatics, Gyro Ball, Low Kick, SmellingSalt, and Stored Power.
2. A value begins at 4096, the following effects are applied to that value in order, each time rounding the value to the nearest integer. Then the power is multiplied by this value, divided by 4096, and rounded half-up.
   1. If the attacker has Technician and the power is 60 or less.
   2. Iron Fist/Analytic/Flare Boost/Sand Force/Toxic Boost/Reckless/Rivalry; Heatproof/Dry Skin; Sheer Force; power-boosting items; Brine/Facade/Fusion Bolt/Fusion Flare/Retaliate/Venoshock; Me First; SolarBeam; Charge; Helping Hand; Water Sport/Mud Sport.

Attack, Defense, Special Attack, and Special Defense are modified by these effects in this order:

1. For physical attacks, use the attacker’s Attack and the target’s Defense. For special attacks, use the attacker’s Special Attack and the target’s Special Defense. The exceptions are as follows:
   • If Wonder Room is in effect, or if the attack is Psyshock, Psystrike, or Secret Sword, but not both, the calculation starts with the Defense stat instead of the Special Defense stat, and vice versa; effects, other than stat stages, that modify Defense will be applied instead of those that modify Special Defense, and vice versa; and the Defense stat stage is used for Psyshock, Psystrike, and Secret Sword.
   • If Psyshock, Psystrike, or Secret Sword are used while Wonder Room is in effect, the calculation starts with the Special Defense stat, the Defense stat stage is used, and other effects that modify Special Defense will be applied.
   • If the attack is Foul Play, the calculation starts with the target’s Attack stat instead of the user’s, and uses the target’s Attack stat stage instead of the user’s.
2. Multiply the stat by the multiplier for its stat stage and round down.
   • If the attack is a critical hit, the Attack or Special Attack stat stage, as applicable, is ignored if it is less than 0, and the Defense or Special Defense stat stage, as applicable, is ignored if it is greater than 0.
   • If the attack is Chip Away or Sacred Sword, the target’s stat stages are ignored.
   • If the attacker has Unaware, the Defense or Special Defense stat stage, as applicable, is ignored. If the target has Unaware, the Attack or Special Attack stat stage, as applicable, is ignored.
   • If a stat stage is ignored, the unmodified stat is used. (For Foul Play, if the Attack stat stage is ignored, the target’s unmodified Attack stat is used. Even if Wonder Room is in effect, if the Defense or Special Defense stat stage, as applicable, is ignored, the unmodified Defense or Special Defense stat, respectively, is used.)
3. If Sandstorm is in effect and the target is a Rock type, Special Defense is modified by 1.5 and rounded half-down.
4. If the attacker has Hustle and the attack is physical, Attack is multiplied by 1.5 and rounded half-down.
5. A value begins at 4096, the following effects are applied to that value in order, each time rounding the value to the nearest integer. Then the Attack or Special Attack, as the case may be, is multiplied by this value, divided by 4096, and rounded half-up.
   • Thick Fat; attacker’s Ability (except Hustle); Flower Gift; attacker’s held item.
6. A value begins at 4096, the following effects are applied to that value in order, each time rounding the value to the nearest integer. Then the Defense or Special Defense, as the case may be, is multiplied by this value, divided by 4096, and rounded half-up.
   • Marvel Scale; Flower Gift; the target’s held item.

After finding the power, Attack, Defense, Special Defense, and Special Attack, the damage becomes equal to:

int(int(int(2*L/5+2)*A*P/D)/50)+2

where L is the attacker’s level, A is the attacker’s Attack or Special Attack value, P is the attack’s power, and D is the target’s Defense or Special Defense value.

The damage is further modified by these effects:

1. If the attack [has more than one target], the damage is multiplied by 3/4 and rounded half-down.
2. During Sunny Day, the damage for Fire-type attacks is multiplied by 1.5 and rounded half-down, and the damage for Water-type attacks is halved and rounded half-down.
3. During Rain Dance, the damage for Water-type attacks is multiplied by 1.5 and rounded half-down, and the damage for Fire-type attacks is halved and rounded half-down.
4. If the attack is a critical hit, the damage is doubled.
5. Damage variance: The damage is multiplied by a random integer from 85 through 100, divided by 100, and rounded down.
6. "Same Type Attack Bonus": If the attack shares a type with one of the attacker’s types, the damage is multiplied by 1.5 (or doubled if the attacker has Adaptability), and is rounded half-down.
7. The damage is multiplied by 1/4, 1/2, 1, 2, or 4, and rounded down, depending on the type matchup of the attack against the target’s types (see the Type Matchup Chart below).
8. If the attacker is burned and doesn’t have Guts, and the attack is physical, the damage is halved and rounded down.
9. If the damage is less than 1, it becomes 1.
10. A value begins at 4096, the following effects are applied to that value in order, each time rounding the value to the nearest integer. Then the damage is multiplied by this value, divided by 4096, and rounded half-up.
    • Reflect/Light Screen; Multiscale; Tinted Lens; Friend Guard; Sniper; Filter/Solid Rock; Metronome item; Expert Belt; Life Orb; damage-reducing Berries; Stomp/Earthquake/Surf/Steamroller.