I would also like to agree that Garticuno isn't S tier, but I think when ranking S tiers in general, they fall into two criteria.
1. Fully warps the tier around it to the point that any team that does not specifically account for it heavily is mediocre.
2. Has a wide variety of sets that are very splashable and all do an amazing job.
Flygon fits into number 2 ofc, I don't think I need to explain why, you could probably mention between 5-8 (I'm avoiding mentioning THAT meme) sets off the top of your head that are all at worst, decent, though a good majority are very good.
So I'd like to talk about the first one, and why munkidori is S tier and will probably always be S tier unless shit like Amuk and Registeel suddenly drop (doubtful).
Every serious team in this tier that isn't HO almost mandates having a steel type, which if we look at samples aside from two HO samples, every one has. And looking at usage stats, for up to round 4 of ssnl (the most current one with stats) there is about 74% usage of the steels combined, with circuit playoffs and last chance having 77% and 76% respectively. Now, the steels do a lot, but the primary thing they do, is be the best answers to munkidori. This is part of the reason that duraludon was so shit for a while, people hadn't discovered the spdef sets and thus dura was a steel that was horrible at checking munki, the one thing that steels are meant to do (though dura is still the worst of the conventional steels at checking munki). You could argue that the steels help check stuff like sylveon, the poisons and the psychics, and they do, but there are other answers to these mons that are abundant in the metagame. Every time somebody tries steel-less, they either 1. Have to use very specific mons together such as av glowbro and scrafty to check it, or 2. simply admit they will lose to it. HO doesn't do this ofc since they can usually offensively check it while punishing its choice lock, but anything else needs to have a solid munki answer, which again is the steels.
This is something that IDT you can really brush away, it is a legitimate thing you need to check off the builder and if you don't, you get fucked. Yes its winrate in ssnl is prob shit rn, but wr is an awful stat to determine viability/brokeness and needs to be looked at with other factors. And by that point, you can probably argue without even discussing winrate (for example rillaboom is at 0 wins in SPL with 12 uses, but instead of argueing its shit cause of the wr, you could argue the structures that rillaboom is usually built around are inconsistent in nature, that sorta thing)
Now, for garticuno, IDT it reaches that level. I would honestly call incin more of an S tier then garti in fact, as a lot of what mgjg (shortening his name since I ain't typing that out) said is true, majority of teams will have sufficient counterplay and it can feel pretty awkward to build with at times. And it 100% does not fit the secondary criteria since its basically cm sets and if you wanna get technical, f-sight pivot (pretty mediocre set) and trick with specs/scarf (incredibly niche).
Also will agree on raising altaria. Cram I think can stay, its really passive into certain shit (read, vapo balance) and is pretty frail. Altaria actually has bulk and natural cure, which is great. I think experimentation with perish song (not even fire spin, just perish song as a standalone move with either wisp or bb) to make sure it isn't setup fodder for shit like guno. You can also use moves like eq which can punish toxt and chandy that think they can be funny and stay in. In general I think alt is underexplored but maybe thats just me lol. Also agree on bootless teams being mediocre. You basically are forced into gligar+zong+wish passer to not autolose to spikestack teams (a very good archetype rn) and thus they can feel awkward to experiment with.
I agree with a good chunk of this, primarily the main logic behind S rankings, just thought I would make a side note.
As a steel-less pilot myself, I must disagree with the argument that steel-less balance is unviable. There is a good number of alternative Munkidori checks suck as the newly dropped Chansey, who can shrug off Toxic Chain, the aforementioned AV Glowbro and cloak Vaporeon, pivot tanks such as AV Meloetta, Swampert and a personal unranked favorite of mine, Milotic, who are all able to take a toxic chain and pivot out before taking meaningful damage, as well as any tera steel user and, less recommended but not unviable, combinations of poison/psychic resists such as Glowbro + Incineroar cores, especially in tandem with protect users. I would thus bring into question the point that every team must account for Munkidori
heavily, as it is a quite simple threat to tick off the list.
But regardless of the answer, I feel like this is an important point to make because a constant thing I hear people say is that teambuilding in SV feels repetitive or restrictive, or difficult in some form. And while pointers such as "always bring a steel" make teambuilding easier for newer players, treating such pointers as gospel is a recipe for repetitive teambuilding and eventual burnout. That is not to say, of course, that having a steel, or at least a tera steel user on your team won't make your job a lot easier, greatly reducing the number of threats you need manually ensure you're checking, such as every fairy, every psychic, stray Cinccinos/Ambipoms and more.
building with garticuno is not miserable. hazardstack and ho are two of the strongest builds in the metagame. garticuno fits seamlessly on each of them. it's not really that hard to support garti either as i outlined in the original post.
much of your suggested counterplay is not reliable or particularly relevant in the metagame. chansey can outright lose to psyshock or tera ghost/ground/elec to mitigate its forms of fighting back, and it's very easy to pressure because it doesnt wanna run boots. scarf chandy and hoopa aren't really used at all (hoopa as a mon entirely is just not very relevant and scarf chandy is cheese/bad). pert is struggling for relevance as is. rhyperior is good agreed, but you should note that freezing glare/psynoise garti 2hkoes pretty easily with a single spike up (thus meaning with any chip), so you have to play it really carefully and ofc keep garti's tera in mind. kilo is pretty dicks but naturally i did state the other ones as being good pending the tera situation. suggesting that people use old and outdated teams is frankly a bit wild lol
being broken=/=s rank by default i agree with. that isn't my point--just part of it. garti warps building around it rn in a way nothing else bar maybe toxt does.
being just outside of top 10 for a few tours and being firmly top 10 for circuit playoffs with an overall positive winrate (if i'm averaging correctly here) is good. but yeah i mean we have mons that'll sit in the high ranks of a tier for months and just not rise like wo-chien in ru did for example (i think it was even a+ at a point on their vr? but it never even rose to the tier). that said this should serve as a reminder that usage stats aren't the end all be all and you are fine to reference them but don't make them some super important conclusion to your argument because imo that's just never a strong way to end it.
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it is a bit contradictory that you say garti is hard to build with, but then go on to prop up hazard removal with the justification that hazard stack will almost always beat superman/boots spam teams. that's just me tho and i think removal is probably the most polarizing concept the tier has rn because you either love it and mons like tsar/cram/alt/cinc frequently or you hate it and just slam your offense teams into people.
To clarify,
1) Suggesting people use old outdated teams is claiming that Galarian Articuno has been accounted for successfully in the builder for months and years, and challenging the other side of the argument to claim otherwise.
2) Every tera mentioned bar ground is niche and means you will be vulnerable to other things, primarily toxic to cripple your setup chances. Listing niche tera options while neglecting nominations of more niche pokemon as counterplay is certainly a choice. Besides, every variant you dropped bar tera ghost should be losing to Chansey's own tera dark, not to mention CM sets.
2.1) Rhyperior will comfortably live two freezing glares with a single spike up (not at +1 I suppose)
2.2) Why are we acting like forcing tera is a bad trade anyway.
3) "Miserable" was a sad choice of words. My point is that the Galarian Articuno player needs to build as carefully as the player defending against it. Neither side has an easy job, and no advantage on builder is claimed for either player. As the balance builder, if you do not have speed control above 95, no special bulk, no steel or tera steel, no phasing or any anti-setup measures, you're going to struggle with WAY more things than just Guno. And, being the Guno player, you need to account for such things too. It's not the "hurr durr" simple teambuilding you are making it out to be.
*3.1) Spikestack does not build itself, unless you are settling for a mediocre team that does not properly cover for the meta.
4) At risk of sounding uninformed, I would like to see more on the aforementioned HO builds you keep cycling back to. I rarely see a Galarian Articuno unless you either, want to punish removal (usually webs, such as
Esteb4ns now illegal webs) or are running some variant of grassy terrain (which is, in my opinion, an inferior choice over Espeon). If you are not punishing defog, there is far less reason to run big Garti, as it does have its share of CM psychics to contend with.
5) I would hope the usage stats are being seen just supporting information, not a super important conclusion. Galarian Articuno has been just ok on paper, and in practice, and there's no reason to hold it in a higher regard than any other teambuilding threat like Basculegion, Flamigo, Munkidori or Chandelure. In less formal terms, there's some insane Galarian Articuno glaze going on that looks more like a "broken toy of the month" syndrome than a proper change from older metas, where this rise was not even a consideration.
6) Galarian Articuno is
more often than not used in the aforementioned boots spam teams, though
you certainly could slot in removal, as I have myself done in the past. I fail to see the contradiction.
I do apologize for derailing the thread with so many messages about the same subject. But I do want to make my stance as clear as possible, and your points make it seem like I did not come across clear enough - not to mention, of course, the points where we clearly just flat out disagree with each other.
*Stance being, Guno is inconsistent, performs unnoteworthy roles outside of spikestack and does not fit either category of S rank. Of course, you can build with it in other archetypes, in the same way you can bring Bellossom to terrain.
in OU is currently B+ rank and as a standalone mon is too weak to do much of anything with how power creeped that tier is. However it is judged off of the archetype it enables and not on the strength of the Mon in a vacuum.
: A -> NUBL
: B -> B+/A-
: UR -> C
: UR -> C
, 
: Higher
: S -> A+
, 
: A+ -> A+
B+ -> A-
