Pokemon Gold and Silver - Damage Calculation

Damage Formula

Raw damage. This is the part of the formula used in the Attack Process.

int(int(int(2×L ÷ 5+2)×A×P ÷ D)/50)+2

where:

• L = Attacker's Level
• A = Attacker's current Attack/Special Attack value
• P = Attack's base damage
• D = Defender's current Defense/Special Defense

For physical attack types (Normal, Fighting, Flying, Poison, Ground, Rock, Bug, Ghost, Steel), use the Attack and Defense values. For special attack types (Fire, Water, Electric, Grass, Ice, Psychic, Dragon, Dark), use the Special Attack and Special Defense values.

Considerations

Occasionally, several situations modify the damage done in the Damage Formula. These considerations are checked in order when figuring the raw damage.

• In internal battles, the badges have the appropriate stat multiplied by 9 and divided by 8 (the Glacier Badge increases just Special Attack).*
• Stat stage modifying attacks modify the appropriate stat (Attack or Defense).*
• If the attacker is burned, halve the Attack value.*
• If the attacker is using Selfdestruct and Explosion, divide the opponent's Defense by 2.
• If the opponent had used Reflect, double the Defense value.*
• If the opponent had used Light Screen, double the Special Defense value.*
• If the attacker is Pikachu with a Light Ball, Special Attack is doubled.
• If the attacker is Cubone/Marowak with a Thick Club, Attack is doubled.
• If the Attack/Special Attack and/or Defense/Special Defense stat exceeds 255, divide both stats by 4 (In GSC, after division, only the low-order byte is retained; e.g. 0x0123 in hexadecimal becomes 0x0023).
• If the opponent is Ditto with Metal Powder, both Defense and Special Defense are multiplied by 1.5.
• If the Attack/Special Attack and/or Defense/Special Defense is 0, it becomes 1.
• Now calculate the damage using the formula above (except the +2 at the end).
• When the attack does a Critical Hit, the calculated damage is doubled.
• If the attacker is holding certain items like Pink Bow and Charcoal, multiply the calculated damage by 1.1 (multiply by 110, divide by 100) if the attacker is using an attack of the appropriate type.
• The damage calculated cannot exceed 997. If it does, the damage becomes 997.
• Add 2 to the calculated damage.

* This effect is ignored if the attack does a critical hit and the attacker's Attack/Special Attack stat stage is less than or equal to the opponent's Defense/Special Defense stat stage.

The Rest of the Formula

The game does not use this part of the formula, but expresses it as other parts of the Attack Process, so it is for information only.

int(int(int(Raw damage×T)×M÷ 10)×R ÷ 255)

T = Same Type Attack Bonus (STAB): If the attacker's attack matches its type (Pikachu using Thundershock), T = 1.5. Otherwise, T = 1
M = Effectiveness modifier (either 0, 2.5, 5, 10, 20, 40); See Battle Chart for effectiveness modifier.
R = Random number between 217 and 255

See also the Damage Calculator.

Critical Hits

The method for determining a Critical Hit is below.

• Set C to 0.
• If Focus Energy is in effect for attacker, add 1 to C.
• If attack is Karate Chop/Razor Leaf/Crab Hammer/Slash/Aero Blast/Cross Chop, add 2 to C.
• If attacker is Chansey with Lucky Punch, add 2 to C.
• If attacker is Farfetch'd with Stick, add 2 to C.
• If attacker has Scope Lens attached, add 1 to C.
• The critical hit ratio is as follows:
  • C = 0: 17/256
  • C = 1: 32/256
  • C = 2: 64/256
  • C = 3: 85/256
  • C = 4 or more: 128/256

A Critical Hit deals two times more damage than usual. Also during a Critical Hit, if the attacker's Attack/Special Attack stat stage is equal to or less than the opponent's Defense/Special Defense stat stage, changes to Attack and Defense due to Reflect, Light Screen, badges, stat stages, and burns are ignored.