Tyranitar @ Choice Scarf  
Ability: Sand Stream  
EVs: 252 Atk / 4 Def / 252 Spe  
Jolly Nature  
- Stone Edge  
- Pursuit  
- Superpower  
- Crunch  

or

Tyranitar @ Chople Berry  
Ability: Sand Stream  
EVs: 248 HP / 80 Def / 180 SpD  
Impish Nature  
- Stealth Rock  
- Stone Edge  
- Pursuit  
- Thunder Wave  

Charizard-Mega-Y @ Charizardite Y  
Ability: Drought  
EVs: 252 SpA / 4 SpD / 252 Spe  
Timid Nature  
- Fire Blast/Flamethrower
- Solar Beam  
- Focus Blast  
- Roost  

Serperior @ Leftovers  
Ability: Contrary  
Hidden Power: Fire  
EVs: 56 HP / 200 SpA / 252 Spe  
Timid Nature  
- Leaf Storm  
- Hidden Power [Fire]  
- Substitute  
- Leech Seed  

or

Keldeo @ Choice Specs  
Ability: Justified  
EVs: 252 SpA / 4 SpD / 252 Spe  
Timid Nature  
IVs: 0 Atk  
- Scald  
- Secret Sword  
- Hydro Pump  
- Icy Wind