Weavile @ Life Orb/Expert Belt
Jolly Nature
EVs: 252 Atk / 252 Spe / 4 HP
-Swords Dance
-Night Slash
-Ice Punch/Ice Shard
-Brick Break
This is probably his most powerful set. Late game, he's your guy. I'd consider using him last, when his counters have been taken care of already. Ice Punch gives your more power, while Ice Shard has priority (it hits first, always). Usually, priority isn't too necessary for him, seeing as his speed is pretty high, but it can be useful. If you use him as a lead, you could consider Focus Sash as an item just to make sure he gets a Swords Dance in.
Jolteon @ Choice Specs
Timid Nature
EVs: 4 def / 252 Spe Atk / 252 Spe
-Thunderbolt
-Hidden Power Ice/Hidden Power Grass/Signal Beam
-Shadow Ball
-Baton Pass
He's fast as sh*t, and with choice specs, he can make a dent. I'd use him as your lead. Hit something hard if Jolteon has a good attack for it, or Baton Pass out of there if you have no counter. Signal Beam should be used only if you don't have Hidden Power Grass or Ice, since it only really gets you coverage on Grass and Dark types, which aren't extremely common.