Wow, a lot of drops and notable rises in Hippowdon and Torkoal (which would have been a better sun-setter partner than Ninetales for Venusaur), gonna just drop some thoughts on how some of these will effect the meta.
Sun is a menace in this tier now, originally only being abused by Shiftry (or Vileplume) but now has Venusaur. Shiftry has more reliable move-set outside of Sun but Venusaur is just a monster in it, with Weather Ball as 100-power Fire-type move. I could see Venusaur being really unhealthy as the only notable weather setter in the tier right now is Gigalith, but Venusaur puts huge pressure on that, so it will require a lot of pivoting. We'll have to see how powerful sun is now, but I have a feeling Venusaur is going to be unhealthy for the tier, in some regard.
Goodra @ Assault Vest
Ability: Sap Sipper
EVs: 248 HP / 168 SpA / 92 SpD
Calm Nature
IVs: 0 Atk
- Draco Meteor
- Surf
- Fire Blast
- Thunderbolt
Not a drop or rise but AV Goodra seems like the best check for Venusaur under sun, being able to take a +2 Sludge Bomb and OHKO 93% of the time with Fire Blast under Sun. The ev spread takes into account Sludge Bomb's 30% chance to poison which can secure possible 2HKOs on max HP Modest Goodra. Overall a good blanket check to even stuff like Noivern, Alolan Raichu, Celebi, Blastoise etc.
168 SpA Goodra Fire Blast vs. 0 HP / 0 SpD Venusaur in Sun: 300-354 (99.6 - 117.6%) -- 93.8% chance to OHKO
+2 252+ SpA Life Orb Venusaur Sludge Bomb vs. 248 HP / 92+ SpD Assault Vest Goodra: 140-165 (36.5 - 43%) -- guaranteed 3HKO after poison damage
Blastoise seems good but with things like Milotic, Mantine and Vaporeon in the their, I'm not too sure... It seems really good against most other stuff in the tier, but it doesn't flat out sweep with the Pokemon I mentioned being common, it will definitely need some support in order to sweep. I could see defensive Rapid Spin having a good spot in the tier as well with Scald/Body Press/Toxic/Rapid Spin as common spin blockers don't like taking a Scald burn such as Doublade.
Raichu FINALLY has a Electric Terrain setter outside of Tapu Koko in OU last gen, where Raichu was simply too weak to compete reliably. Pincurchin offers Spikes and Toxic Spikes for chip damage on checks to Raichu, as well as Memento if the time comes for a sweep. Raichu under Electric Terrain is the fastest Pokemon in the tier (out speeding even scarf Noivern) and even outside of Electric Terrain, it's speed tier is fantastic, only being outsped by Inteleon, Noivern, Alolan Persian and Scarfers. Nasty Plot/TBolt/Psychic/Focus Blast hits everything in the tier for at least neutral damage expect for Celebi. I think Raichu will be pretty solid in this tier.
Same old Alolan Ninetales, it sets up broken screens and let's powerhouses such as Necrozma and Linoone to break or sweep teams. Although with other weathers being allowed in the tier now, that might change. Most likely outcome though is Ninetales will run Hail in it's moveset to mindlessly outplay other weather setters as they switch in, just like in OU.
This thing has a niche as a Suicide Lead with Steel Beam, much like Excadrill does in OU. Outside of that, I don't know why you would run this.
This Pokemon got Swords Dance this generation which is a HUGE boon. It's great speed tier of base 105 and solid 100 base attack stat with a reliable boosting and good coverage of Wild Charge and High Horsepower/Drill Run make it a great Fire-type sweeper. Heavy-Duty Boots can also increase it's longevity without having to run Morning Sun. I could also see this paired on sun teams with Venusaur or on Aurora Veil teams.
It's niche to it's Galarian cousin is that it isn't weak to Steel-types, which has some merit with Doublade, Lucario and Cobalion the tier. Other than that, it's outclassed.
I think this is the best Pokemon we got from tier shift, it's just so reliable now especially with Pursuit being removed from the game. It beats Pokemon like Milotic, Rhyperior, Weezing-Galarian and even Umbreon with the right set. It does have to worry about Knock Off and First Impression (now that is has been more distributed), but I think Celebi is one of, if not THE best mon in the tier.
Veil BellyDrum, that's what this Pokemon does. Although the 50% berry nerfs are quite a big hit to this thing.
Solid Rocker especially due to it's being able to beat other all other Rockers now that Hippo rose as this thing dropped. SD could also be really strong but without Z-Moves it's not as notable as it once was. Solid Pokemon all around.
Virizion seems actually pretty good, now that it got Megahorn it can beat Celebi. It obviously is walled by Doublade or Weezing and is outsped by likes of Noivern but I could see SD or CM Virizion (with Air Slash now as well) being solid in the tier.
I feel like despite it having a higher attack stat and a way to break Doublade, Decidueye is not as good as Virizion. It loses to Umbreon unlike Virizion, it's slower so it has to run Sucker Punch, isn't as bulky as Virizion... The only niche I see with this Pokemon is that it can trap with Spirit Shackle. I guess it's also a Defogger that also Spin Blocks, but the only notable spinners are Avalugg and Blastoise which have ways of punishing it via Ice-type moves or burning with Scald with Blastoise. Maybe a Nasty Plot set? With Giga/Hurrican/Shadow Ball? We'll see.
I'm not sure about Incineroar. On one hand it looks amazing with the Heavy-Duty Boots, pivoting around with Parting Shot and checking Doublade, but with the handful of Fighting-types in the tier... ehhh... I want to see how this turns out, I hope it's UU material this gen.
Probably the best out of the three Alola starters, now it has access to Calm Mind. Choice Specs also just as dangerous last gen but also a notable set I noticed while it was used in OU was Whirlpool + Perish Song (sort of like Azumarill) which can useful in removing Pokemon like Umbreon, Milotic, Vaporeon which have no way of threatening it. I believe the set is Whirlpool/Perish Song/Protect/Rest? That way they can avoid Toxic, though I could Sub + Scald replacing Protect and Rest.
Necrozma keeps getting moves added to it's movepool, now having access to Dragon Dance. Offensive Rocker, SD + 3 Attacks, DD + 3 attacks, SD Rock Polish, CM... It's just so versatile. Also with Alolan Ninetales in the tier, it can be run on Veil where it truly shines as a sweeper. I have high hopes for Necrozma this gen.
This tier is getting shaken up, one way or another, I suspect some things might be quick banned (looking at you Venusaur) and tested later, but we'll see. I'm really excited for UU this gen, because while a lot of people are fear mongering Stall coming back, I think we're far from it at this point lol.