This is a little different from the other Frosmoth sets.
Gen 8 PU
Frosmoth @ Heavy-Duty Boots
Ability: Ice Scales
EVs: 248 HP / 164 SpD / 96 Spe
Calm Nature
- Ice Beam
- U-turn / Quiver Dance
- Rest
- Sleep Talk
This set is intended to check most of the special wallbreakers and sweepers in the tier. Ice Beam is STAB. U-Turn is for pivoting. Rest is for healing. Sleep Talk is so you won't be vulnerable while you're asleep. Quiver Dance can be used over U-Turn if you want to setup and boost your stats. 248 HP is to help with your bulk. 96 Speed EVs allow you to outspeed max speed Modest Alolan Exeggutor. The rest of the EVs go to special defense.
Teammates
You'll definitely want Pokémon who can check fire and rock types, so Pokémon such as Toxicroak and Jellicent are greatly appreciated. Pokémon who can't take special hits that well can appreciate Frosmoth being able to take those hits for them. Pokemon such as Regirock, Basculin, Centiskorch, etc can help Frosmoth as they can check Pokémon such as Aggron and Archeops, who check ice types like Frosmoth.
Defensive Calcs
252 SpA Heliolisk Thunderbolt vs. 248 HP / 164+ SpD Ice Scales Frosmoth: 54-64 (15.7 - 18.6%) -- possible 6HKO
Possible damage amounts: (54, 54, 55, 56, 57, 57, 58, 59, 59, 60, 60, 61, 62, 63, 63, 64)
+2 252 SpA Ribombee Moonblast vs. +2 248 HP / 164+ SpD Ice Scales Frosmoth: 52-62 (15.1 - 18%) -- possible 6HKO
Possible damage amounts: (52, 53, 54, 54, 54, 55, 56, 57, 57, 58, 58, 59, 60, 60, 61, 62)
+2 252 SpA Life Orb Toxicroak Focus Blast vs. +2 248 HP / 164+ SpD Ice Scales Frosmoth: 81-96 (23.6 - 27.9%) -- 86.1% chance to 4HKO
Possible damage amounts: (81, 82, 83, 84, 84, 86, 86, 88, 88, 90, 90, 92, 92, 94, 94, 96)
+2 252 SpA Life Orb Toxicroak Sludge Wave vs. +2 248 HP / 164+ SpD Ice Scales Frosmoth: 64-76 (18.6 - 22.1%) -- possible 5HKO
Possible damage amounts: (64, 65, 65, 66, 67, 68, 68, 69, 70, 71, 72, 72, 73, 74, 75, 76)
252 SpA Choice Specs Whimsicott Hurricane vs. 248 HP / 164+ SpD Ice Scales Frosmoth: 107-126 (31.1 - 36.7%) -- 70.3% chance to 3HKO
Possible damage amounts: (107, 108, 109, 110, 112, 113, 114, 115, 117, 118, 119, 120, 122, 123, 124, 126)
Enjoy!