Every ability

Defiant

This Pokémon's Attack is raised by 2 for each of its stats that is lowered by a foe.

Standard ability
4
Pokémon
Hidden ability
13
Pokémon

In detail

This Pokémon's Attack is raised by 2 stages for each of its stat stages that is lowered by an opposing Pokémon.

Pokémon that can have it

17

Standard ability4Any one caught or hatched may have it

Hidden ability13Only one with its hidden ability has it