Its infuriating, and I lose far more than I win against Mewtwo ex. Counters, Ive tried numerous. My fun Dragonite deck has some utility here, and well-timed Draco Meteors can win you the battle in ...

some of the best counters are Shadow Mewtwo, Shadow Heatran/Groudon, Kyogre/Mega Swampert. You can use Shadow Mewtwo to go against Skorupi and Nidoqueen. But since Sierra also has Drapion and ...