I'm going to be posting the GSC PU sample teams shortly, but while I work out a couple details I wanted to make a post-GSCPL personal viability ranks post.
Anyone who watched GSCPL PU games will notice the fall off of Hitmontop

, last voted close to unanimously #1 on the VR. Over time Top has felt simply less mandatory, being a good switch in to a huge portion of the tier but often finding itself struggling to make real progress. Despite that, Top still has many good matchups, is never a bad pick and is also seeing a bit of a resurgence of Curse sets including some cool non-sleep talk brings in the tour. I can't rightfully put it in S tier right now, but it's still pretty much a top 5 level mon.
Venomoth

and Elekid

have emerged as the clear top 2 in my mind, with Veno the definite #1 imo as the best utility and progress mon in the tier while Kid is still the fastest key meta mon and one of the hardest mons to properly switch into to the extent that its main check is itself.
More of a hot take but maybe not, is Seaking

in 3rd, I personally feel no other mon can supplant it from this spot. The level of compression and threat this mon provides is unmatched, with its high natural bulk allowing it to be one of the few reliable (outside of hp elec crits) Seadra switch ins, a good Veno check that lasts through the game, a late game wincon and a mon that can race some of our curse users. While most of the time not wanting to deviate from SD/Return/Rest/Talk, the capacity to switch to a mixed set or run curse cannot be overlooked.
Delibird

I've finally budged and thought of this as a top tier mon in my time playing and testing for GSCPL. It's no longer a dead slot that runs spikes, but a genuinely useful (but frail and limited switch ins) mon that can make progress and defines a whole teamstyle. While I've placed grasses quite low in my VR a lot of players are relying on them right now and Delibird is thriving.
A tier is loaded up with the top 3 curse normal checks (Rhyhorn, Magcargo, Gastly), the chief curse normal guy (Noctowl), the best breaker in the tier (Cubone) and one of the best utility/progress mons in Sneasel

, who I feel is sorely underrated and underused. Screech Sneasel is one of the best mons available on Spikes which I also view as the best playstyle in the tier - it's a threat vs non-magcargo rocks, an off-curse check in itself which allows you to flex your team outside of running the same curse rock types or Gastly, it's capable of stalling Seadra/Veno/Elekid even through status and is just an all round threat. Gastly

is also on the rise big time right now, feeling very consistent as a curse normal check that doesn't take chip to do it, with a bit more speed and initial power while also having quite a bit of flex with its moveset. It's much more limited in switch ins than Rhyhorn + Magcargo, but is nonetheless really useful on more aggressive builds, enough that I think it belongs pretty close to the top 10.
All 3 main grasses (Tangela

, Bayleef

, Sunflora

) find themselves in the B tier for me with Tangela rising above them in B+ due to being the best check to Cubone and Rhyhorn. I feel that grasses offer a lot of utility but are under too much pressure to get their job done half the time, often ending up a near-dead slot praying it doesn't get full para'd every time it comes in. A well placed, and lucky, grass type is a top 10 level mon but you simply don't get that in a lot of games right now I feel.
Other smaller notes:
- Abra
feels like it's improving with people picking up Rest Talk, could be better than we feel.
- Murkrow
continues its drop as it just simply doesn't do the things its stats promise it would.
- I might be underrating Clefairy
though I feel it lacks parity with some of the meta due to relying on twave para while often needing to eat para itself.
- Geodude
and Wartortle
both feel cemented now as "not joke mons", in some matchups winning the spike war is as good as winning the game.
Baton Pass

is still unhealthy without Spider Web. Our best mon in the tier being a Curse Passer is a volatile state for the tier to be in, and Agilipass to Cubone just autowins a number of non Tangela or Roar Rhyhorn matchups. I feel that Baton Pass is both unhealthy and offers nothing worth preserving, it would be nothing but a gain to ban that move and move on with our lives.
I am still of the mind that it would be great to take our next steps to consider phased unfreezing of NU low tier mons with E tier mons (Arbok and Azumarill) being first phase and evaluating from there if we want to introduce D tier mons. I haven't changed my mind particularly from my
tiering hub posts but I can also understand people who are happy enough with the current state of PU that they don't see a need to change things.
That's all for now
