Whimsicott.
Stats - 60/67/85/77/75/116
Abilities - Prankster (1), Infiltrator (2), Chlorophyll (H)
Notable Moves
- Taunt
- Leech Seed
- Substitute
- Encore
- Switcheroo
- Moonblast
- Hurricane
- Giga Drain
- Knock Off
- Memento
- Tailwind
Pros
- Has access to Prankster, Leech Seed, and other utility.
- Can be used at level 1 due to evolving via an item.
- Is quite fast even without a Prankster boost.
- Has access to Infiltrator if you want a more offensive moveset or to just be meaner to Dark-type Pokemon in general.
- Offensive sets have a chance to wipe out Great Tusk or other prevalent Dragon- or Fighting-Types from the question entirely using Moonblast.
- Can fit on Sun with Chlorophyll.
Cons
- Suffers a DREADFUL 4x Poison weakness normally.
- Dark-types completely shut you down if you run into one and are running a Prankster set.
- Has had a bad reputation and was in PU for the last two generations.
- Not exactly the best later-game unless you know what you're doing.
Analysis and Tera Potential
While Whimsicott has been here since Generation 5, it has suffered badly with typing and viability in these past few metagames. It suffers a weakness to some potent types in the forms of Fire, Steel, and Poison, but since we're bringing our favorite little fluffball into a tera-filled metagame, those problems will be no more. With Tera Water, Whimsicott gets rid of FOUR weaknesses, turning three of them into resists, in exchange for Grass and Electric weaknesses. This could be BIG for Whimsicott, because Steel has been EXTREMELY potent in the forms of Kingambit and Heatran (though one is obviously more reliant on steel-type attacks on a resist than the other..), and its 4x Poison weakness is just GONE.
There's also threats in the Fire-Type category with Ceruledge, Cinderace, Iron Moth, and other extremely potent Pokemon in OU, which Whimsicott can now resist with Tera Water and a possibly bulkier set to be able to do what it can. Yes, those pokemon have BATSHIT INSANE offensive stats, but that's why we gave Whimsicott U-Turn, didn't we?
Alternatively, there's more offensive tera types such as Fairy or Flying, which can boost Moonblast or Hurricane respectively, on the off-chance you run an offensive Whimsicott. If you run an offensive Whimsicott, you might want to run it on Sun with Chlorophyll, as Whimsicott simply can't outrun some of those mons that you might want dead.
And Whimsicott has access to Tera Grass AND Solar Beam to get rid of absolutely every water-type named Dondozo or rock-type named Garganacl, and there's many sun benefactors here, too, so Whimsicott could be quite alright on Sun. Also, it could slip Tera Fire on to deal with
And in conclusion, with the bits of research and knowledge I have applied to this thread, I have come up with exactly three sets for this Pokemon, despite my thoughts of it not going anywhere past at least RU this time around.
Potential Sets
Set 1
Whimsicott @ Choice Scarf
Ability: Prankster
Tera Type: Water
EVs: 252 HP / 4 Def / 252 SpD
Calm Nature
IVs: 0 Atk
- Switcheroo
- Leech Seed
- Substitute
- Encore
This set is my average Whimsicott SubSeed set. Is it okay? Maybe, I've used it a bit and sometimes it was okay. This was prior to Gen 9 however, so changes may be prevalent. But it's really fun for certain Pokemon.
Whimsicott @ Choice Scarf
Ability: Infiltrator
Tera Type: Water
EVs: 252 HP / 4 Def / 252 SpD
Calm Nature
IVs: 0 Atk
- Switcheroo
- Leech Seed
- Substitute
- Encore
(Same set, but for Dark-Types.)
Set 2
Whimsicott @ Choice Specs
Ability: Infiltrator
Tera Type: Fairy
EVs: 4 HP / 252 SpA / 252 Spe
Timid Nature
IVs: 0 Atk
- Moonblast
- Giga Drain
- Hurricane
- Switcheroo
A Whimsicott set in the more offensive range. Teras are indeed interchangeable, as you can make it Tera Flying for big Hurricane boosts (making it able to be fit onto RAIN somehow, too, although not really recommended yet), and Switcheroo for surprise shutdowns on setup sweepers such as Manaphy or Dragonite, which are very prevalent in our current meta as NOTORIOUS setup sweepers.
Set 3
Whimsicott @ Choice Specs
Ability: Chlorophyll
Tera Type: Grass (or fire if you want to, solar beam is actually strong enough without tera grass)
EVs: 4 HP / 252 SpA / 252 Spe
Modest Nature
IVs: 0 Atk
- Moonblast
- Solar Beam
- Tera Blast
- Switcheroo
A sun-fit Whimsicott set. You can change Tera Blast for another move or make Whimsicott just Tera Fire itself for alternative coverage versus Kingambit or other Steel- and/or Grass-Types in our current metagame. As Whimsicott has Chlorophyll here, and we've got Ninetales and Torkoal as some Sun benefactors, I'm sure that Whimsicott would be able to fit well here SOMEHOW as a main-line attacker if you REALLY have no other options.
My Conclusion? Will Whimsicott stay OU?
Will Cott be OU for more than a month? Absolutely not, but I'm sure it'll be absolutely GOATED in lower tiers, where there's less threatening sweepers everywhere for Whimsicott itself to run around in with its prankster-setting antics. Yes, Tera Water will be its "saving grace" as it removes four weaknesses as well as gives it a FAR better defensive typing, and has some REALLY mean abilities and utility to combine into an interchangeable plaything (plus, Klefki's still here too) to just be able to hopefully ruin someone's life with a single cute little fluffy ball of pure MEMERY.