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Mega Altaria being statused isn't helpful to a facade sweep though S:. Glare would obviously paralyze it to death, then Zygarde can always coil up, sub up, DD, or switch out to something that can take a hit like an arceus fairy. Anything that can really burn Mega Altaria such as Arceus Poison or Arceus Fairy also just beat it straight up. I'm mainly liking the bulky set right now.
Just a thought, on the M-Altaria team (Idfk which, the DD one), it gets Facade, I'd imagine a 140 BP x 1.2 fairy stab hitting like a truck after one DD, could use it to blanket Zyg's Glare unless you're afraid of parahax fucking you over, wdy think?