Here it is, the rain beast.
Rotom-W @ Life Orb
EVs: 64 Def / 252 SAtk / 64 SDef / 128 Spd
Timid Nature (+Spd, -Atk)
- Hydro Pump
- Signal Beam
- Hidden Power [Ice]
This is the set that isn't going to see a lot of use, but works amazingly.
Thunder and Hydro Pump is the rain boosted, crazy beast STAB moves you get, with Bug and Ice coverage.
Bullky sweeping EVs, with Life orb.
Rotom-W @ Choice Specs / Scarf
EVs: 64 Def / 252 SAtk / 64 SDef / 128 Spd or 252 SAtk / 252 Spd / 4 Hp
Timid Nature (+Spd, -Atk) / Modest Nature (+SAtk, -Atk )
- Volt Switch
- Hydro Pump
- Hidden Power [Ice] / Thunder
Lots of ways to twist and turn through this set, but this is the standard issue Rotom-W.
Volt Switch lets him scout , with guarenteed speed if using Scarf, and with guarenteed power with Specs.
Hydro Pump is STAB, and rain boosted, Specs ( possibly ) boosted as well.
Trick is to choice your opponent into something they don't wanna be choiced into.
The last slot is pure coverage with HP Ice, or more STAB that won't switch you out of play with Thunder.
Overall, this may be one of the top 10 best pokemon to use on a rain team, amazing dual typing, Dual STAB Thunder and Hydro Pump this thing just murders.
Rating for the rain - 10/10