Diamond Battle Tower Double Battle (with trade backs)
Streak: 78 Wins
Garchomp @ Lum Berry
Ability: Sand Veil
EV's: 252 Atk 252 Speed 4 HP
Zapdos @ Yache Berry
EV's: 252 Sp.Atk 252 Speed 4 HP
Metagross @ Occa Berry
Ability: Clear Body
EV's: 244 HP 252 Atk 4 Def 4 Sp.Def 4 Speed
Abomasnow @ Choice Scarf
Ability: Snow Warning
EV's: 22 HP 236 Speed 252 Sp.Atk
Hidden Power [Ground]
Usually with a combination of Discharge/Heat Wave + Earthquake/Rock Slide I can take out all the opponents team. Crunch for any Bronzong, and Thunderbolt for reliable STAB when I don't want to attack Zapdos' partner. Against any ice pokemon (Walrein/Glaile especially) I always Protect with Zapdos and Rock Slide with Garchomp as he won't help much anyway. Then I take them out with Heat Wave or Bullet Punch. I try not to bring in Abomasnow as he is usually more of a help then a hinderance. (Snow Cloak/Ice Body).
I can't remember how I lost because I did this about 2 months ago, but I am trying a new attempt and am currently on 35 wins.