You may do 100 more damage. If you do, during your opponent's next turn, this Pokémon takes 100 more damage from attacks (after applying Weakness and Resistance).
Abilities
Counterattack
Ability
If this Pokémon is your Active Pokémon and is damaged by an opponent's attack (even if this Pokémon is Knocked Out), put 4 damage counters on the Attacking Pokémon.
Disclaimer: The following data is based on sale history from a third party source. Data is updated about every 5 days. This data does not serve as a value guarantee.