When the Pokémon has any of its stats lowered by an opponent, its Attack stat is boosted by 2 stages.
Defiant (Japanese: まけんきCompetitive Spirit) is an Ability introduced in Generation V.
Effect
In battle
When a stat of a Pokémon with this Ability is lowered by an opponent, its Attack is increased by two stages. Defiant will not activate if the Pokémon with this Ability lowers its own stats (such as with Close Combat) or if its stats are lowered by an ally, but will activate if its stats are lowered as a result of its barrier being broken in a Max Raid Battle.
If multiple stats are lowered (such as by Memento or Venom Drench), Defiant activates for each stat lowered.
If one stat is lowered by more than one stage (such as by Charm or Eerie Impulse), Defiant will only trigger once.
Defiant activates before a held White Herb. If the Pokémon no longer has any negative stat stages after Defiant is applied, the White Herb will not have the chance to activate.