Calub is a trainer from the kanto region. He is the champion of the mega league a league similar to the pokemon league but formed from the most powerful mega pokemon trainers. He oftens appears in the series helping out the main character.
Mewtwo -> Mega-mewtwo Y
this pokemon is Calub mega pokemon he encountered it at a young age and battled it and caught. It is not always with him as it does not like being confined it is his second most powerful pokemon
Moves: Psystrike, psychic, energy ball, aura sphere
moves:Thunderbolt shadow ball pin missile