There is no Rain Abuser set in the OP.
I personally go with :
Tapu Koko @ Life Orb
+Spe -Def nature
252 SpA, 252 Spe, 4 SpD
Thunder
U-Turn
HP Ice
Brave Bird
Thunder hits insanly hard and has 100% accuracy, U-Turn so you can pivot against Grounds or A-Marowak, HP Ice for Landorus / Gliscor /...