Mewtwo-Mega-Y @ Life Orb  
Ability: Sheer Force  
EVs: 252 HP / 252 Def / 252 SpA / 252 SpD / 252 Spe  
Timid Nature  
IVs: 0 Atk  
- Psychic  
- Earth Power  
- Moonblast  
- Strength Sap  

Chansey (F) @ Eviolite  
Ability: Imposter  
EVs: 252 HP / 252 Def / 252 SpD / 252 Spe  
Calm Nature  
- Shore Up  
- U-turn  
- Stealth Rock  
- Anchor Shot  

Xerneas @ Toxic Orb  
Ability: Poison Heal  
EVs: 252 HP / 252 Atk / 252 Def / 252 SpA / 252 SpD / 252 Spe  
Modest Nature  
IVs: 0 Atk  
- Moonblast  
- Spikes  
- Quiver Dance  
- Strength Sap  

Giratina @ Griseous Orb  
Ability: Prankster  
EVs: 252 HP / 252 Atk / 252 Def / 252 SpA / 252 SpD  
Relaxed Nature  
IVs: 0 Spe  
- Core Enforcer  
- Strength Sap  
- Haze  
- Spectral Thief  

Groudon @ Red Orb  
Ability: Electric Surge  
EVs: 252 HP / 252 Atk / 252 Def / 252 SpD / 252 Spe  
Impish Nature  
- V-create  
- Anchor Shot  
- Bolt Strike  
- Shore Up  

Kyogre-Primal @ Assault Vest  
Ability: Regenerator  
EVs: 252 HP / 252 Atk / 252 Def / 252 SpA / 252 SpD  
Sassy Nature  
IVs: 0 Spe  
- Revelation Dance  
- Rapid Spin  
- Spectral Thief  
- U-turn