Absolute evil

Blissey @ Choice Scarf
Ability: Serene Grace
Level: 50
EVs: 252 HP / 4 SpA / 252 Spe
Hasty Nature
- Rock Slide
- Ice Beam
- Thunder
- Flamethrower

Aerodactyl-Mega @ Aerodactylite
Ability: Tough Claws
Level: 50
EVs: 4 HP / 252 Atk / 252 Spe
Jolly Nature
- Rock Slide
- Sky Drop
- Ice Fang
- Protect

Meowstic @ Mental Herb
Ability: Prankster
Level: 50
EVs: 252 HP / 4 SpA / 252 Spe
Timid Nature
- Thunder Wave
- Swagger
- Psychic
- Quick Guard

Thundurus @ Sitrus Berry
Ability: Prankster
Level: 50
EVs: 252 HP / 4 SpA / 252 Spe
Timid Nature
- Thunder Wave
- Swagger
- Taunt
- Thunderbolt

Klefki @ Leftovers
Ability: Prankster
Level: 50
EVs: 252 HP / 4 Def / 252 SpA
Modest Nature
- Thunder Wave
- Swagger
- Substitute
- Draining Kiss

Cinccino @ King's Rock
Ability: Skill Link
Level: 50
EVs: 4 HP / 252 Atk / 252 Spe
Jolly Nature
- Tail Slap
- Bullet Seed
- Rock Blast
- Protect