Zygarde-Complete @ Leftovers  
Ability: Unaware  
EVs: 252 HP / 252 Atk / 252 Def / 252 SpA / 252 SpD / 252 Spe  
Impish Nature  
- Topsy-Turvy  
- Crabhammer  
- Toxic  
- Sunsteel Strike  

Dialga @ Assault Vest  
Ability: Regenerator  
EVs: 252 HP / 252 Atk / 252 Def / 252 SpA / 252 SpD / 252 Spe  
Sassy Nature  
- Core Enforcer  
- Moongeist Beam  
- Nuzzle  
- Spectral Thief  

Mewtwo-Mega-Y @ Leftovers  
Ability: Magic Bounce  
EVs: 252 HP / 252 Atk / 252 Def / 252 SpA / 252 SpD / 252 Spe  
Timid Nature  
IVs: 0 Atk  
- Photon Geyser  
- Moongeist Beam  
- Light of Ruin  
- Quiver Dance  

Groudon @ Red Orb  
Ability: Download  
EVs: 252 HP / 252 Atk / 252 Def / 252 SpA / 252 SpD / 252 Spe  
Adamant Nature  
- V-create  
- Precipice Blades  
- Sunsteel Strike  
- King's Shield  

Kyurem-Black @ Safety Goggles  
Ability: Refrigerate  
EVs: 252 HP / 252 Atk / 136 Def / 252 SpA / 252 SpD / 252 Spe  
Adamant Nature  
- Fake Out  
- Extreme Speed  
- Dragon Hammer  
- Earthquake  

Arceus @ Leftovers  
Ability: Soundproof  
EVs: 252 HP / 252 Atk / 252 Def / 252 SpA / 252 SpD / 252 Spe  
Impish Nature  
- Perish Song  
- Strength Sap  
- Spiky Shield  
- Anchor Shot