User blog comment:Unmei Suiheisen/Are Elemental/Damage boosts stackable?/@comment-26447088-20170214030320/@comment-26447088-20170216033423

Healers aren't really a big concern in this game besides Fortress Frenzy or Belly of the Beast, where Heal over multiple turns units are the main go-to.

I think you should aim for a unit with Defense down/HP down next. If you got her last event, Fafnir was a solid DEF down unit with good ATK stats.