Originally Posted by
Unregistered
Use Amaterasu. Her damage is irrelevant, her skills are far more important and open up more soul options for you like Joan with black propaganda or Morded with trial. Using Balor with Morded is meaningless so she can easily be replaced. Although slightly conflicted as the next event is water.
For eidolons you have, you can use Dullahan instead of Echidna. If you want a bit more damage, sure, keep her, but this isn't about doing damage cause then I'd tell you to replace your ssr defender weapons with sr lv20 assault weapons. Or you can just use a friend with Dullahan with your Echidna and see if that's enough to last, if not double Dullahan is one of your best bets.
Being a 42k+ atk dark team, you have more than enough stats to clear ragnarok difficulty stages regardless of element. Dropping some damage for better survivalbility is a better option, until you get more kamihimes.