I would recommend against it, but if you're able to balance out your Pokémon count so that you can still easily and consistently get them in play and set up to attack, then I suppose it could be okay. As an M Mewtwo Y player, I find that having at least three helps get things set up quicker, and it allows for more consistency in starting with it, too. Try to get at least one more of each card if you can, as it helps the deck a lot, in my opinion.I'm trying to build a M Mewtwo deck but only have 2 M Mewtwo and 2 Mewtwo EX. Can I get away with running only 2?