Awesome team - its very creative. Tera Steel Specs Hydreigon is pretty underrated for sure. I used it for a bit on a shittier team and did notice that its speed tier and defensive qualities are pretty nice - its got a nice MU into Gholdengo, Kyurem, and Gambit, and can easily pressure some other common Pokemon such as Samurott-H, Pecharunt, Landorus-T, Ceruledge and a few other staples. That combined with its near immunity to hazards and I think its definetly a sleeper pick. Comboing it with band Ogerpon-TM is a nice call since you get a similarly strong breaker that also doubles as speed control for some of its more problematic MUs like Dragapult, Ting-Lu, Garg, etc. I'm not SUPER high on Tinkaton rn but I will admit I love its synergy with Hydreigon on this team. Glad to see you saw potential in Hydreigon - espicially given how potent it was in early metas like DLC1 and Pre-home.
There are a few MUs I'd like your advice in however, as I've been struggling against them.
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This mon is a pain in the ass to switch into, paralyzes everything, pressures Tusk, can Volt out of Alo into a Dark-type partner for big damage + paraylze it to interupt its pivoting game.
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Been finding this guy impossible to switch into - all the mons with longevity on this team are fucked by Salt Cure or get completely walled and there's very little stopping Garg from spamming Salt Cure + maybe setting up Rocks. I had to swap Pecharunt to be the Covert Cloak NP set just to deal with this, but that comes with its own drawbacks (on that note, could make it tera Electric to also help with Zap but might be overkill).
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Outspeeds and 1-2HKOes everything with CB Tera Blast Ghost, with Hydreigon also being a bit of a crappy resist here because of U-turn / Darts. Only counterplay I've found is making favorable treads with Tera Ogerpon, but if they have something like Corv as a partner, its really tough.
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Probably the hardest MU on this list. AV is extremely annoying because it is difficult to setup Rocks against it + it walls Hydreigon, and while Tinkaton can steal its boots / AV, its a double edge sword. Additioanlly, a well-played Tornadus-T can play around this by going for Heat Wave as Tinkaton swaps in, which is bad since TInkaton is needed for other mons on the Torn users team.
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If this gets in on Tusk, its over. Mola can mirror Coat it IG at high health, but Serp can also just as easily beat it with cheese + BS from other sets like Sub, Tera Blast Fire fries Tinkaton, and Pecha will be severly weakened trying to handle it. Additionally, Glare is horrific to deal with.
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Its very difficult to apply pressure to prevent Deoxy's Speed from setting up screens, though I suppose if you know its screens you can just pressure it with Hydreigon or Tera Grass Ogerpon. I am a bit hesistant Turn 1 Teraing against these however, as they usually are filled to the brim with out mons that can sweep at a moment's notice.
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- Well played Iron Boulder can sweep very easily because it outspeeds the speed control on this team & wearing down Balloon Tinkaton is easy. Usually Tera Steel Hydreigon and Tusk are fine, but this mon also has the set variation to goob those as well, which is difficult to sus out.
Probably a few more that I'm missing, but these were some of the primary mons I've been struggle handling.
Still, congrats on the peak!