Heracross-Mega @ Heracronite  
Ability: Guts  
EVs: 248 HP / 144 Atk / 88 Def / 28 Spe  
Adamant Nature  
- Close Combat  
- Pin Missile  
- Bulldoze  
- Protect  

Greninja @ Choice Specs  
Ability: Protean  
EVs: 4 Atk / 252 SpA / 252 Spe  
Hasty Nature  
- Hydro Cannon  
- Blizzard  
- Hidden Power [Fire]  
- Gunk Shot  

Gyarados-Mega @ Gyaradosite  
Ability: Intimidate  
EVs: 252 HP / 60 Atk / 12 Def / 80 SpD / 104 Spe  
Adamant Nature  
- Dragon Dance  
- Outrage  
- Stone Edge  
- Waterfall