Standard (Registeel) @ Leftovers  
Ability: Clear Body  
EVs: 252 HP / 196 SpD / 60 Spe  
Careful Nature  
- Thunder Wave or Toxic 
- Seismic Toss  
- Explosion  
- Counter  

Special (Registeel) @ Leftovers  
Ability: Clear Body  
EVs: 192 HP / 4 Def / 252 SpA / 60 Spe  
Bold Nature  
IVs: 2 Atk / 30 SpA  
- Thunder Wave  
- Hidden Power [Grass]  
- Ice Punch  
- Seismic Toss  

Double Status (Registeel) @ Leftovers  
Ability: Clear Body  
EVs: 252 HP / 216 SpD / 40 Spe  
Careful Nature  
- Thunder Wave  
- Toxic  
- Seismic Toss  
- Explosion  

Quirky (Registeel) @ Leftovers  
Ability: Clear Body  
EVs: 252 HP / 160 Atk / 96 SpD  
Careful Nature  
- Curse  
- Amnesia  
- Rollout or Return or Hidden Power Steel (rollout and steel can't take bulky waters, return can't take ghosts, opposing registeel kind of stops all of them)
- Rest