Ness and Mewtwo destroy everyone easily... except Sackboy.
Look, I don't care if you have guys who have killed gods or have giant rocket launchers, you're not going to do anything when psychics destroy you from inside your own mind. The only character that stands a chance is Sackboy, who is essentially a god who can create or destroy anything.
However, if we go with canon Pokemon Trainer, we may have a game with Sackboy vs Arceus.
Kratos' mind is already essentially a bag of angry cats anyways. Your psychics cant do anything to his mind that would change his undying rage, and that rage is what keeps him going. Its like instinct to him at this point. He doesn't need his mind for that.
Lightning is a terrible character. Deal with it. Official Riku of the PASBR board.
Pokemon Trainer with Arceus is a good argument. Except for the fact, that the Pokemon Trainer in SSBB only has 3 pokemon, ivysaur, squirtle and charizard. None of which could stand up to hardly anyone on the playstation side.