Yveltal @ Heavy-Duty Boots  
Ability: Dark Aura  
EVs: 252 HP / 252 Def / 4 SpD  
Impish Nature  
- Foul Play  
- U-turn  
- Defog  
- Roost  

Blissey (F) @ Utility Umbrella  
Ability: Serene Grace  
EVs: 252 Def / 4 SpA / 252 SpD  
Calm Nature  
IVs: 0 Atk  
- Ice Beam  
- Confide  
- Aromatherapy  
- Soft-Boiled  

Groudon @ Leftovers  
Ability: Drought  
EVs: 176 HP / 96 Atk / 180 Def / 56 Spe  
Impish Nature  
- Precipice Blades  
- Stone Edge  
- Rock Polish  
- Swords Dance  

Necrozma-Dusk-Mane @ Rocky Helmet  
Ability: Prism Armor  
EVs: 252 HP / 4 Atk / 252 Def  
Impish Nature  
- Earthquake  
- Toxic  
- Stealth Rock  
- Moonlight  

Ho-Oh @ Heavy-Duty Boots  
Ability: Regenerator  
EVs: 252 HP / 84 Atk / 104 Def / 52 SpD / 16 Spe  
Impish Nature  
- Sacred Fire  
- Brave Bird  
- Thunder Wave  
- Whirlwind  

Marshadow @ Choice Band  
Ability: Technician  
EVs: 252 Atk / 4 SpD / 252 Spe  
Adamant Nature  
- Poltergeist  
- Close Combat  
- Spectral Thief  
- Shadow Sneak