Hippowdon @ Leftovers  
Ability: Sand Stream  
EVs: 252 HP / 4 Def / 252 SpD  
Careful Nature  
- Stealth Rock  
- Earthquake  
- Toxic  
- Slack Off  

PLUS

Skarmory @ Rocky Helmet
Ability: Sturdy  
EVs: 252 HP / 72 Def / 184 Spe  
Impish Nature  
IVs: 0 Atk  
- Spikes  
- Iron Defense  
- Body Press  
- Roost  

OR

Skarmory @ Shed Shell  
Ability: Sturdy  
EVs: 248 HP / 248 Def / 12 Spe  
Impish Nature  
IVs: 0 Atk  
- Spikes  
- Body Press  
- Toxic  
- Roost