Gengar

[GiMYz]

I really like Icy Wind Gengar

Gengar @ Focus Sash
Ability: Levitate
Level: 50
EVs: 4 HP / 252 SpA / 252 Spe
Timid Nature
- Shadow Ball
- Sludge Bomb
- Icy Wind
- Will-O-Wisp

252 SpA Gengar Icy Wind vs. 4 HP / 0 SpD Garchomp: 108-128 (58.6 - 69.5%) -- guaranteed 2HKO
252 SpA Gengar Icy Wind vs. 4 HP / 0 SpD Landorus-T: 112-136 (67.8 - 82.4%) -- guaranteed 2HKO
252 SpA Gengar Icy Wind vs. 4 HP / 0 SpD Salamence: 104-124 (60.8 - 72.5%) -- guaranteed 2HKO

You can get a huge amount of damage thanks to Gengar's high Special attack, while slowing down your opponents.