Ampharos-M @ Leftovers
Ability: Static
Nature: Modest (^SpAtk vAtk)
EV Spread: 252 SpAtk, 252 Spd, 4 HP
Thunder
Dragon Pulse
Hyper Beam
Thunderbolt
Lanturn @ Damp Rock
Ability: Volt Absorb
Nature: Timid (^Spd vAtk)
EV Spread: 252 Spd, 128 SpDef, 128 Def
IVs: 31 Speed
Rain Dance
Ion Deluge
Thunderbolt
Hydro Pump
Luxray @ Life Orb
Ability: Intimidate
Nature: Adamant (^Atk vSpAtk)
EV Spread: 252 Atk, 252 Spd, 4 HP
Spark
Crunch
Thunder
Ice Fang
Basically, Lanturn sets up a Rain Dance so Thunder for Luxray & Ampharos has 100% Accuracy, and then uses Ion Deluge to make Ampharos Hyper Beam murder everything. Also, once set up, Lanturn has trouble fainting with Aqua Ring + Thunders from Luxray & Ampharos for Volt Absorb.