Mono Water

Gyarados-Mega @ Gyaradosite
Ability: Intimidate
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly Nature
- Waterfall
- Crunch
- Earthquake
- Dragon Dance

Pelipper @ Choice Specs
Ability: Drizzle
EVs: 252 SpA / 4 SpD / 252 Spe
Modest Nature
- Hydro Pump
- Hurricane
- Ice Beam
- U-turn

Azumarill @ Choice Band
Ability: Huge Power
EVs: 252 Atk / 4 Def / 252 Spe
Adamant Nature
- Liquidation
- Play Rough
- Knock Off
- Aqua Jet

Kingdra @ Life Orb
Ability: Swift Swim
EVs: 252 SpA / 4 SpD / 252 Spe
Modest Nature
IVs: 0 Atk
- Surf
- Draco Meteor
- Ice Beam
- Hydro Pump

Seismitoad @ Leftovers
Ability: Water Absorb
EVs: 248 HP / 252 Def / 8 SpD
Relaxed Nature
- Scald
- Earthquake
- Toxic
- Stealth Rock

Tapu Fini @ Leftovers
Ability: Misty Surge
EVs: 252 HP / 4 SpA / 252 Spe
Timid Nature
IVs: 0 Atk
- Moonblast
- Nature's Madness
- Taunt
- Defog