Generation Vii
Merciless
The Pokémon’s attacks become critical hits if the target is poisoned.
Detailed Effect
This Pokémon's moves critical hit against poisoned targets.
Pokémon With Merciless
2 canonical Pokémon forms can have this Ability.
Generation Vii
The Pokémon’s attacks become critical hits if the target is poisoned.
This Pokémon's moves critical hit against poisoned targets.
2 canonical Pokémon forms can have this Ability.
Mareanie 
Toxapex