Mewtwo-Mega-Y @ Psychic Seed  
Ability: Magic Bounce  
EVs: 252 HP / 252 Def / 252 SpA / 252 SpD / 252 Spe  
Timid Nature  
IVs: 0 Atk  
- Psychic Terrain  
- Photon Geyser  
- Rapid Spin  
- Taunt  

Rayquaza-Mega @ Life Orb  
Ability: Magic Guard  
EVs: 252 HP / 252 Atk / 252 Def / 252 SpA / 252 SpD / 252 Spe  
Hasty Nature  
- Core Enforcer  
- Brave Bird  
- Head Smash  
- Light of Ruin  

Rayquaza-Mega @ Draco Plate  
Ability: Contrary  
EVs: 252 HP / 252 Atk / 252 Def / 252 SpA / 252 SpD / 252 Spe  
Hasty Nature  
- Protect  
- V-create  
- Draco Meteor  
- Dragon Ascent  

Gengar-Mega @ Spooky Plate  
Ability: Mold Breaker  
EVs: 252 HP / 252 Def / 252 SpA / 252 SpD / 252 Spe  
Modest Nature  
IVs: 0 Atk  
- King's Shield  
- Quiver Dance  
- Judgment  
- Secret Sword  

Xerneas @ Power Herb  
Ability: Fairy Aura  
EVs: 252 HP / 252 Def / 252 SpA / 252 SpD / 252 Spe  
Bold Nature  
- Moonblast  
- Wish  
- Geomancy  
- Protect  

Kyogre-Primal @ Assault Vest  
Ability: Mega Launcher  
EVs: 252 HP / 252 Def / 252 SpA / 252 SpD / 252 Spe  
Modest Nature  
- Origin Pulse  
- Dark Pulse  
- Ice Beam  
- Water Pulse