The best thing to do is indeed to duck when she's mid-air with a full mast , as she can't be dodged or blocked any other way. The only other advice I can give you is to bash her as hard as possible when she "lands" for a few turns as it's the only time where you'll get any consistent damage. Also she's damagable on the same turns as she deals her own damages to you (so choose to hit when she's mid air) while she isn't fully excited yet.