best mmx answer (Doublade) @ Eviolite  
Ability: Fur Coat  
EVs: 252 HP / 252 Atk / 252 Def / 252 SpA / 252 SpD  
Relaxed Nature  
IVs: 0 Spe  
- Spectral Thief  
- Shore Up  
- stealthrockspikes  
- U-turn  

why (Steelix-Mega) @ shedshellsafetygoggles  
Ability: Fur Coat  
EVs: 252 HP / 252 Atk / 252 Def / 252 SpA / 252 SpD  
Relaxed Nature  
IVs: 0 Spe  
- Will-O-Wisp  
- Shore Up  
- Haze  
- Thousand Waves  

very situational tbh (Slowbro-Mega) @ Shed Shell  
Ability: Fur Coat  
EVs: 252 HP / 252 Def / 252 SpA / 252 SpD  
Relaxed Nature  
IVs: 0 Atk / 0 Spe  
- Will-O-Wisp  
- Shore Up  
- scaldspikes  
- U-turn