Swampert-Mega @ Shed Shell  
Ability: Wonder Guard  
EVs: 252 HP / 4 Def / 252 SpD  
Sassy Nature  
IVs: 0 Atk / 0 Spe  
- Magic Coat  
- Aromatherapy  
- Recover  
- Parting Shot  

Gyarados-Mega @ Dread Plate  
Ability: Huge Power  
EVs: 176 HP / 252 Atk / 4 SpD / 76 Spe  
Adamant Nature  
- Pursuit  
- Water Shuriken  
- Sucker Punch  
- Gastro Acid  

Giratina @ Safety Goggles  
Ability: Prankster  
EVs: 248 HP / 252 Def / 8 SpD  
Bold Nature  
IVs: 0 Atk  
- Defog  
- Encore  
- Curse  
- Recover  

Xerneas @ Iron Plate  
Ability: Wonder Guard  
EVs: 180 Def / 252 SpA / 76 Spe  
Modest Nature  
IVs: 0 Atk  
- Shell Smash  
- Judgment  
- Freeze-Dry  
- Lava Plume  

Steelix-Mega @ Lum Berry  
Ability: Magic Bounce  
EVs: 248 HP / 8 Def / 252 SpD  
Sassy Nature  
IVs: 0 Atk / 0 Spe  
- Roost  
- Stealth Rock  
- Scald  
- Parting Shot  

Zekrom @ Lum Berry  
Ability: Mold Breaker  
EVs: 144 Atk / 56 Def / 252 SpA / 56 Spe  
Rash Nature  
- Dark Void  
- Shell Smash  
- Bolt Strike  
- Spacial Rend