Scarfed Gastly (Gastly) @ Choice Scarf  
Ability: Levitate  
EVs: 252 SpA / 4 SpD / 252 Spe  
Timid Nature  
IVs: 3 Atk / 30 SpA / 30 SpD  
- Shadow Ball  
- Sludge Bomb  
- Hidden Power [Ground]  
- Trick

Stallbreaker Gastly (Gastly) @ Black Sludge  
Ability: Levitate  
EVs: 252 SpA / 4 SpD / 252 Spe  
Timid Nature  
IVs: 0 Atk  
- Substitute  
- Taunt  
- Shadow Ball  
- Sludge Bomb

SubSplit Gastly (Gastly) @ Life Orb  
Ability: Levitate  
EVs: 252 SpA / 4 SpD / 252 Spe  
Timid Nature  
IVs: 0 Atk  
- Substitute  
- Shadow Ball  
- Sludge Bomb  
- Pain Split