I dont have Kerria either. And I have not yet got to the Boss. Was mashing out the event map like crazy to finish all the event item sheets and started on the Nidhorog maps only yeasterday. Should tackle him today and see how we do. Might have to play around the setup for my team 3 as the 5* crit team is really not up to par with the rest of the squad.

Tis true I wanted her a lot, but since she doesnt fit into any of the teams I am building currently obtaining her is on hold for the moment (unless some lucky gacha graces me with a good pull that is.).
Need to bang out my 1st Counter team, then maybe start on the second but leave it mixed with some of the left over Evade girls, and move on to the fun part - as in, the second Crit team
(yes I am a simple man, I like damage being done and red numbers appearing on the screen. No need for fancy shmancy stuff like Debuffs, Evasions, and Solar Blasts )