Belly Drum Sweeper
Chesnaught @ Shell Bell
Trait: Bulletproof
Nature: Impish (Def+,SpA-)
EVs: 252 Def, 252 Atk, 4 HP
Belly Drum
Drain Punch
Spiky Shield
Leech Seed OR Rock Slide
Belly Drum gives four Swords Dances instantly, but you need to heal after use. To take care of that, set up Leech Seed first. After the Belly Drum, either Drain Punch (if your opponent is slower than you) or Spike Shield yourself. ( Scope out their move pool, if they're hitting physically, deal some damage. Very risky, but if you manage a OHKO, you're set. Sweep'em with Drain Punches, staying at high health. Alternatively, replace Leech Seed with Rock Slide for coverage against Flying, Fire, and Ice types, which can hurt Chesnaught. Please vote me up!