Suggested by Sonic Mewtwo is probably the strongest Pokemon of them all. He’s proven himself time and time again in combat. The only Pokemon that are even close to him would be other heavy hitters like Deoxys and Pikachu and both have had trouble with him in the past. Pichu’s speed is usually quite an asset, but against Mewtwo’s psychic abilities it will be of little use. Mewtwo also has great levels of speed in his mega form which makes him even more unbeatable. Mewtwo wins.