Gorebyss

Swift Swim
Speed doubles in rain.
Type Tier
Water UU
Level 100 Statistics (see level 5, 50, 100)
Min- Min Max Max+
HP
55
- 251 314 -
Atk
84
183 204 267 293
Def
105
221 246 309 339
SpA
114
237 264 327 359
SpD
75
167 186 249 273
Spe
52
126 140 203 223
  • Underused

Overview

Using Gorebyss with Spikes can work, as the sight of Rain Dance users trigger a switch to Water-types, and Spikes + Hidden Power Grass will hurt. After you do this once your opponent will most likely keep the Pokémon in so you can freely Surf it. Hydro Pump is always an option over Surf, but that accuracy hurts.

Name Item Nature

Rain Dance Sweeper

Leftovers Modest
Moveset EVs
~ Rain Dance
~ Surf / Hydro Pump
~ Ice Beam
~ Hidden Power Grass / Hidden Power Electric
56 HP / 252 SpA / 200 Spe

As you can see, Gorebyss has awesome Defense and Special Attack, while having crappy Speed and HP. So let's compare it to its rival, Omastar:

HP: 70—Attack: 60—Defense: 125—Special Attack: 115—Special Defense: 70—Speed: 55

So Omastar has nearly same Special Attack, 5 less Special Defense, but a solid 15 more HP, which more than covers the Special Defense, and 20 more Defense. Gorebyss lacks the Rock-type, which can be a pain or your lifesaver; no Normal resistance hurts a lot, but Omastar is weak to the common Earthquake. Due to having a pure Water-type, you can't switch Gorebyss in on resistances, as Ice and Water are its only resistances, and you would get Toxiced by the common Waters.

Rain Dance boosts your Speed and powers up Surf, turning Gorebyss into an offensive powerhouse.

Name Item Nature

Baton Pass

Leftovers Bold
Moveset EVs
~ Baton Pass
~ Surf
~ Agility
~ Amnesia / Iron Defense / Ice Beam
252 HP / 136 Def / 60 SpD / 60 Spe

Baton Passer. Watch out for Electrics and phazers.

Other Options

It gets Confuse Ray; if you have luck, you can try it. Maybe it can give you a turn to Rain Dance.

EVs

190 Speed (200 Speed EVs) is needed for the Rain Dancer in UU. You can go lower if you aren't afraid of Electrode and Persian. Max Special Attack, and put the rest in HP. For the Baton Passer, max HP, balance out the defenses, and put Speed wherever to beat something after an Agility (there are tons of things you can do with it).

Checks and Counters

The only way to stop this is using a Water-type with decent Special Defense, like Blastoise or Walrein (Omastar doesn't count, thanks to the part Rock typing). Light Screening Hypno and Tricking with Grumpig can help you. Shedinja is always an option.