Mewtwo is not the strongest Pokemon, but it is certainly one of the most powerful. Mewtwo is a legendary psychic Pokemon. He evolves from Mew, which can only be obtained through an event distribution in the game. Mewtwo is one of the most powerful pokemon, and is difficult to obtain if you're not playing the game. Mewtwo has few weaknesses with moves like Psystrike, Psychic, Shadow Ball, and Hyper Beam.