Goddess Briyella
Banned deucer.
I'm fairly certain that the only "mixed" thing that sounds viable for Mega Altaria is running Fire Blast alongside Pixilate-boosted Return and Earthquake on a Dragon Dance set. I know there's also Draco Meteor, but this move cannot be spammed and Altaria has no way to boost its special offense.
And Audino, Mega or not, will definitely outclass Mega Altaria as a team supporter regardless of its several resistances, because Altaria does not have Wish or Knock Off.
And Audino, Mega or not, will definitely outclass Mega Altaria as a team supporter regardless of its several resistances, because Altaria does not have Wish or Knock Off.