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: I think these two pokemon are better than all the rest by a sizeable margin, the only third mon they are somewhat relative to is Alomomola but I believe that is a clear third best mon. I change my opinion quite often on which of these is the actual top 1, atm I'm leaning towards zama but that could change very easily.
Gholdengo is up here because nothing warps the tier around it like it does. The set variety on this pokemon is insane, it can viably hold half a dozen items across three main "groups" of sets, offensive plot, defensive and scarf, although it's not the hardest thing in the world to predict the set at preview. The answers to each set aren't too different, for offensive sets you just need a strong supereffective attacker, like a volcarona, samurott, great tusk, lopunny, etc. For defensive sets you mainly need a twave absorber, which is just any ground bar great tusk, ragning bolt or zapdos, or something like a kingambit that doesnt really mind getting thunder waved much. More specialized sets such as choice scarf or shuca berry generally get checked naturally by the other answers, you just need to be aware of the possibility of your gliscor getting tricked or your great tusk getting traded out after ghold eats a headlong rush. Even with how much the tier is centered around gholdengo, it will get some value in every single game, be it checking your zamazenta or blowing up your landorus-t with corkscrew crash
Zamazenta's essential role is being the very best speed control option in a tier heavily lacking them. Options such as mega lopunny and choice scarf urshifu have heavily fallen out of favor the past few months due to the near omnipresence of moltres and zapdos to punish their spamming of contact moves and rocky helmet being as prevelent as ever. Zamazenta does still have this issue to an extent but uses stone edge to avoid contact while still threatening these birds and can choose to use boots to mitigate being worn down over time, althought it opts to use different items a bit more often nowadays, such as fightinium z, life orb, darkinium z and a personal favorite of mine, assault vest. The power boosting items give it that extra little boost it needs to become a real threat in the early game. Av lets it 1v1 stuff like tornadus, scarf lele, diancie, latios, and be a better check to kyurem and volcarona. Other competition for speed control is limited by having to use choice scarf, such as tapu lele and gholdengo, or are reliant on booster energy such as iron valiant and iron moth, who are also quite subpar pokemon. Delvng into the niche territory there are options such as meowscarada, blacephalon, and kartana which do bring some unique value but have very significant drawbacks which prevent them from being truly good.
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: This is by far the most uninteractive pokemon in the tier and requires next to no skill to wield to very high effectiveness. This pokemon doesn't really check anything in particular other than assault vest sets checking gholdengo and the increasingly important fire types, its just a very good blanket check to most attackers that has to be careful of certain pokemon like ogerpon-w, ferrothorn and most substitue users that can punish its passivity. Selecting proper partners that can check these pokemon can allow alomomola to simply spam flip turn all game and get unlimited pivots to any breaker and never dying.
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: The main reason this thing is ranked so high is fire types. So many balances need to compress a fire and water resist into one slot and dragonite is by far the best option, other options such as raging bolt and kyurem don't have the longevity and excelent defensive profile that dragonite boasts. It is a gigantic momentum sink and dragon dance variants can't afford to run an adamant nature on balance which makes it a suboptimal setup sweeper, but it simply has 0 real dragon type competition and the demand for them makes it extremely good by default. Bulky dragon tail variants are quite a solid option on the proper hazard stack teams that I believe is quite heavily underexpored, allowing dragonite to invest significantly more into its bulk alongside an adamant nature while not losing much due to it already being a relatively weak dragon dance sweeper.
Where dragonite really thrives as more than just a pseudo defensive piece piece is on offense teams. It can afford to run more agressive sets backed by excelent removal options such as diancie, hatterene, iron treads and terapagos, with items such as loaded dice and dragonium z to become a truly terrifying setup sweeper that doesn't rely on roost, opening the door for it to utilize its vast movepool, featuring options such as outrage and loaded dice, bolstered by the aforementioned items, Flyinium Z boosted fly, stone edge, encore, fire punch and substitute, most of which are not usually seen on balance teams.
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: Still the best setup sweeper in the tier, not much to say. Knock off is a broken item, supreme overlord is a broken ability and kingambit has the bulk and power to wield both of these traits alongside swords dance and sucker punch to become the perfect endgame sweeper while having a significant amount of utility in the early and midgame thanks to its defensive profile bolstered by leftovers.
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: Static is an extremely broken ability that allows this pokemon with average physical bulk check almost every single physical attacaker in the tier. Its just perfectly bulky enough to be a solid ogerpon answer provided it doesn't get crit, and in exchange for all this just good enough bulk it gets a powerful hurricane that can dissuade most ground types from attempting to block its volt switch even while uninvested, allowing for very easy pivoting into threats such as samurott or specs tapu lele
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: Very very hard to switch into unless you are using mola, appreciates gliscor not being quite as amazing as it once was since its a p good switchin. Has a quite nice defensive profile that checks volcarona and yard once if played properly and clicks buttons very freely.
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: Spikes toxtect is still good, I'm a big fan of sd and defog sets asw. Not much has rlly changed with this mon other than it becomming slightly worse
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: Ngl half the reason I'm making this post is so I can talk about this mon. Dragonium Z is the best rocker in the tier, will get at least rocks or a kill, often gets both and more if properly played. The popularization of subscale + loaded dice is awesome, you get to fodderize alo, pex and fish hurricane misses on zapdos which just gives it so many more setup opportunities. I'm a huge fan of helmet chomp, you get rocks and spikes and dragon tail everything around, and get to be a one or two time answer to every physical attacker, even stuff like weavile you get to force a trade against. Spdef is still p good, not huge on a dragon that can't check volcarona but it def has a very good niche.
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:Scarf is scarf and does the same thing it has done since sm. I'm moreso big on cm and aoa sets, again will talk about av (i love this item) which gives it that little extra bulk to trade vs almost every special attacker and is not choiced which a lot of players can wrongly assume.