Mewtwo

Mewtwo debuted in Pooh's Adventures of Pokémon: The First Movie. He was created by scientists at laboratory on New Island. Mewtwo destroyed the lab because he thought the scientists were using him as a experiment. Later, Giovanni trained Mewtwo to control his psychic powers. But after he learned why Giovanni was training him to serve him, Mewtwo destroyed his lab. Mewtwo vowed to destroy Earth for betraying him, he rebuilt New Island. Later, Pooh and the others traveled to New Island for a big Pokémon showdown created by Mewtwo. After making Pokémon clones, there was a big showdown between clones and originals. Ash Ketchum stopped the showdown by standing in the middle of the stadium between Mew and Mewtwo's beams of psychic energy. Then, Mewtwo learned that Ash was a person who valued all Pokémon born or created. Mewtwo and the Clones left to find a place where they could live in harmony and peace and used his psychic power to return Pooh and friends home and wipe out the memory of the fight on the trainers.

Later, in Pooh's Adventures of Pokémon: Mewtwo Returns, Mewtwo took Christopher Robin, to be safe from Giovanni. Then, Pooh and his friends reunited w/ Ash, Misty, Brock, and Pikachu to find him at Purity Canyon. Team Rocket's combat unit arrived to take Mewtwo and his clones, and claim Mt. Quena as a new laboratory. Pooh and his pals freeed Mewtwo from Giovanni's machines and revived him in the spring water. After that Mewtwo erased Giovanni's memory, spared the memories of Pooh and his friends, returned Christopher Robin to them, and decided to live w/ them but at Skull. Thus, Mewtwo became the father figure to Pooh and his pals.