Board Thread:Versus Battles/@comment-27151416-20170821015503/@comment-28644276-20170821022020

"All who draw the danmaku will die by the danmaku."

...Either Inconclusive or Iesua. They seem pretty even (both being final bosses as well, so in the same place in the hierarchy and prowess with Danmaku) but Iesua does have a Spellcard (I think the timeout one) where she does something very similar to Amakasu with Ragnarok summoning: Mumumu and two other beings (forgot their names) appear and apparently do battle reenacting some kind of war in heaven.

They launch their spellcards all at once - Demise: Angel's Brazier, Demise: Dragonslayer and Demise: He who Eats the God - and stay in that battle for a long while. And even if you last enough to deal with that, Iesua still comes back for one last spellcard after that.

All in all, thinking Iesua outlasts Byakuren here.