I mean you technically don't see Hellblade Glavenus actually vaporizing mountains in
gameplay, nor do we see other super powerful monsters levelling islands in gameplay. We primarily get these kinds of feats via lore and statements from canon sources. Like, Saber from the Fate series is rated at Mountain level for her standard strikes because of scaling to Hercules and Lancelot, but she never is seen blowing away the city she is in with these strikes and we still rate her as such. IDK why it's different here.
1. [
[1]] Here you can read that when a stronger monster is fighting Agnaktor, volcanic activity AND eruptions become far more common as they fight, implying that they occur as a result of their clash (And that it isn't just Agnaktor using this to drive off other monsters because this is all a side-effect of the battle). On top of this, Agnaktor have destroyed whole villages before.
2. The monsters in MH:W don't get out of that fall from the top of the Ancient Tree unscathed. If the monster has taken sufficient damage, the fall can even kill them, meaning they most certainly don't come out unscathed.
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[2]] The Kirin calc DOES yield 7-A for Kirin, but here it states that Kirin is as powerful as other Elder Dragons, meaning that it could likely scale to the Island Level that most other ED's would get from Hellblade Glavenus vaporizing mountains or Oroshi Kirin freezing shit.
4. [
[3]] Kushala Daora also dispersing this storm all the way to the horizon in nearly an instant also should be calced imo, could yield some good stuff
5. IDK if the Zorah Magdaros exploding and destroying the New World can really be applicable because that was only going to happen when all of it's life energy flooded into the Everstream, and that's why they diverted it to the ocean; because then it would simply die out there and not cause the everstream to blow the New World apart. Perhaps I am missing something here, but aside from that Zorah Magdaros was indeed responsible for "tectonic movement" upon its first fight near the start of the game.
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[4]]A standard Lagiacrus in-game is stated to make entire oceans surge with electricity, which could possibly be calcable? Maybe not? Seems a tad vague, but I figure I would drop it here.
7. Barioth (Not to be mistaken for Barroth) can create small-scale tornadoes in combat. IDK how important this would be in a calcing sense tho
This is all I can think of at the mo. Had no idea that this thread was happening lol