Noivern is really good though. Like, really good.
Give it taunt, draco meteor, air slash, and roost. Bam, super mon.
No Boomburst? 140 power, 100% accuracy, ignores Substitutes. Contrast with Hyper Beam at 150 power, 90% accuracy, and a mandatory recharge turn. Boomburst is quite entertaining. I still prefer Crobat, the original speedy taunter, though. Taunt/Roost/Brave Bird/Cross Poison, especially nowadays with Fairy types, and Infiltrator to bypass Substitutes.
Ya it's really good. I knew I was forgetting something.
I think it's another case of 4 moveslot syndrome. I like taunt because Noivern is so fast, so you can send it out first and check things like Smeargle. If you gave it a lum berry it could check Klefki too. I like draco meteor because not only is it a really powerful STAB, but it helps remove almost every single dragon in the game. I say helps because you normally have to bring those dragons down to 70%hp or so. It can also remove things like Greninja and other weaker but fast nuisances in one blow from 100 to 0.
I like air slash because it's another STAB and I generally don't run more than one flying type, so I like having the coverage to deal with fighting types. The flinch chance is also really nice as if you're in a pinch against a Dragonite for example... you can't OHKO it with draco meteor. So your best hope to avoid dying is to air slash, hope for a flinch, and draco meteor.
I think it's a toss up between roost and boomburst. I like both. I chose roost because I forgot boomburst haha.
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By the way, did you guys know Volcarona only really has one weakness? You can't kill it with water as its SpD is way too high. With simple prediction, the Volcarona can prepare one quiver dance beforehand and only take 25% hp damage from a hydro pump. After that it's just a matter of using quiver dance and roost. Maybe throw a will-o-wisp on the enemy in the meantime. The only way to kill it is with rock.
My current OU team seems like it'd be supremely weak to water given that I have Charizard, Volcarona, Tyranitar, Garchomp, and Archeops. However, neither Tyranitar or Volcarona really care about water so it's a bit of a bait. No one can resist using a water attack on those guys and it gives me free turns to set up. 3x quiver dance Volcarona is invincible.