Groudon @ Soft Sand  
Ability: Drought  
EVs: 168 HP / 252 Atk / 8 SpD / 80 Spe  
Adamant Nature  
- Swords Dance  
- Precipice Blades  
- Stone Edge  
- Rock Polish  

Necrozma-Dusk-Mane @ Rocky Helmet  
Ability: Prism Armor  
EVs: 248 HP / 252 Def / 8 Spe  
Impish Nature  
- Dragon Dance  
- Sunsteel Strike  
- Earthquake  
- Morning Sun  

Yveltal @ Heavy-Duty Boots  
Ability: Dark Aura  
EVs: 248 HP / 72 Def / 188 SpD  
Careful Nature  
IVs: 20 Spe  
- Knock Off  
- U-turn  
- Sucker Punch  
- Roost  

Ferrothorn @ Leftovers  
Ability: Iron Barbs  
EVs: 252 HP / 252 Def / 4 SpD  
Impish Nature  
- Leech Seed  
- Iron Defense  
- Body Press  
- Spikes  

Eternatus @ Sitrus Berry  
Ability: Pressure  
EVs: 252 HP / 160 SpD / 96 Spe  
Timid Nature  
IVs: 0 Atk  
- Dynamax Cannon  
- Flamethrower  
- Toxic  
- Recover  

Calyrex-Shadow @ Choice Scarf  
Ability: As One (Spectrier)  
EVs: 4 Def / 252 SpA / 252 Spe  
Timid Nature  
IVs: 0 Atk  
- Astral Barrage  
- Psyshock  
- Will-O-Wisp  
- Aromatherapy