Balanced Core
Ferrothorn + Keldeo
+
Ferrothorn and Keldeo are a good core that work together stopping a lot of the OU threats. Ferrothorn doesn't like going up against things like Heatran, Magnezone, Mega Scizor, Sableye, Mega Lopunny, Azumarill, DD Mega Altaria and Landorus-T. Scarf Keldeo...