It's not as good as we would want for it to be, but with Karen coming up soon and Dragonite EX next month it will become more and more reliable.
Besides Brilliant Arrow / Despair Ray M Gardevoir EX goes along well vs matches where you don't have the weakness advantage.
Just like few of the members here have said, the best / easiest way to crush M Mewtwo EX decks is with the new M Gardevoir EX (STS). The 2 energy Despair Ray attack OHKO's him.
This past weekend I went to a LC and out of 5 rounds I faced 3 M Mewtwo Decks. Deck 1 and 3 I had problems setting my...
Xernias BREAK / Giratina EX for now. Maybe i'll run a 2-2 line of Trubish / Garbodor.
Once Karen and Dragonite EX are released I will go back to M Gardevoir EX (STS) deck.