Slaking @ Choice Band  
Ability: Truant  
EVs: 252 Atk / 4 Def / 252 Spe  
Adamant Nature  
- Ice Punch  
- Fire Punch  
- Giga Impact  
- Earthquake  

Gyarados-Mega @ Gyaradosite  
Ability: Intimidate  
EVs: 248 HP / 44 Atk / 42 Def / 174 Spe  
Adamant Nature  
- Dragon Dance  
- Earthquake  
- Crunch  
- Taunt  

Magearna @ Fairium Z  
Ability: Soul-Heart  
EVs: 248 HP / 44 SpA / 216 Spe  
Modest Nature  
IVs: 0 Atk  
- Calm Mind  
- Iron Defense  
- Pain Split  
- Fleur Cannon