Mewtwo is a legendary Psychic-type Pokémon that is weak against Bug, Dark, and Ghost moves. When battling against Mewtwo, it is recommended to use Pokémon that have a Fast Attack and a Charged Attack of one of these types to deal as much damage as possible. Some recommended Pokémon and moves to use when battling against Mewtwo include Gengar, Houndoom, Tyranitar, Weavile, Genesect, Darkrai, Origin Giratina, Hydreigon, Chandelure, Yveltal, and moves prioritizing Dark attacks and powerful Psychics. Mewtwo is also stronger against Fighting-type enemies and other Psychic types, so it is best to avoid using these types when battling against it.