Mewtwo-Mega-Y @ Choice Specs  
Ability: Psychic Surge  
EVs: 252 HP / 252 Def / 252 SpA / 252 SpD / 252 Spe  
Timid Nature  
IVs: 0 Atk  
- Psycho Boost  
- Psystrike  
- Moongeist Beam  
- Volt Switch  

Zekrom @ Magnet  
Ability: Electric Surge  
EVs: 252 HP / 252 Atk / 252 Def / 252 SpA / 252 SpD / 252 Spe  
Naive Nature  
- Bolt Strike  
- Volt Switch  
- Soak  
- Roost  

Gyarados-Mega @ Steelium Z  
Ability: Volt Absorb  
EVs: 252 HP / 252 Atk / 252 Def / 252 SpA / 252 SpD  
Sassy Nature  
IVs: 0 Spe  
- Knock Off  
- Anchor Shot  
- Volt Switch  
- Milk Drink  

Diancie-Mega @ Pixie Plate  
Ability: Pixilate  
EVs: 252 HP / 252 Atk / 252 Def / 252 SpA / 252 SpD / 252 Spe  
Hasty Nature  
- Extreme Speed  
- Boomburst  
- Knock Off  
- Stealth Rock  

Magearna @ Leftovers  
Ability: Magic Bounce  
EVs: 252 HP / 252 Def / 252 SpA / 252 SpD / 132 Spe  
Sassy Nature  
IVs: 0 Spe  
- Core Enforcer  
- Defog  
- Heal Order  
- U-turn  

Chansey @ Choice Scarf  
Ability: Imposter  
EVs: 252 HP / 252 Atk / 252 Def / 252 SpA / 252 SpD  
Relaxed Nature  
IVs: 0 Spe  
- Metal Burst  
- Whirlwind  
- Soft-Boiled  
- Trick