Mewtwo-Mega-Y @ Mewtwonite Y  
Ability: Insomnia  
EVs: 24 HP / 28 Def / 240 SpA / 216 Spe  
Timid Nature  
IVs: 0 Atk  
- Nasty Plot  
- Psystrike  
- Focus Blast  
- Ice Beam  

Marshadow @ Life Orb  
Ability: Technician  
Tera Type: Ghost  
EVs: 252 Atk / 4 Def / 252 Spe  
Jolly Nature  
- Bulk Up  
- Spectral Thief  
- Low Kick  
- Shadow Sneak  

Zacian-Crowned @ Rusted Sword  
Ability: Intrepid Sword  
Tera Type: Fighting  
EVs: 252 Atk / 4 Def / 252 Spe  
Jolly Nature  
- Swords Dance  
- Play Rough  
- Wild Charge  
- Close Combat  

Groudon-Primal @ Red Orb  
Ability: Drought  
EVs: 248 HP / 140 Def / 120 SpD  
Relaxed Nature  
- Stealth Rock  
- Overheat  
- Precipice Blades  
- Rock Tomb  

Terapagos-Terastal @ Heavy-Duty Boots  
Ability: Tera Shell  
Tera Type: Stellar  
EVs: 248 HP / 104 Def / 72 SpD / 84 Spe  
Bold Nature  
- Tera Starstorm  
- Toxic  
- Rapid Spin  
- Roar  

Arceus-Ground @ Earth Plate  
Ability: Multitype  
Tera Type: Poison  
EVs: 248 HP / 124 Def / 136 Spe  
Timid Nature  
IVs: 0 Atk  
- Toxic  
- Judgment  
- Ice Beam  
- Recover