Unfortunately, unless all the DPSs can time their Skills perfectly to dodge attacks, Ciella demands a healer of some kind. Wellisanne can work, but if you’re running Ranged allies they have to huddle up which makes this fight trickier.
Good thing I built Lowen up as soon as he appeared
A good chunk of High Mercury picks are viable here too, but in my opinion slower characters are gonna have a harder time without good i-frame skills. Lin You in particular has it real rough imo, the AoEs feel like they’re just fast enough to force roll spam.
If you want easy picks, Lowen is actually the best option despite his heal not curing Freeze. He charges skills faster than W!Xania and his S2 works as both a pseudo heal and a buff for Ciella’s burst attacks.
Also yes, you have to take out Ciella’s Crystal Arrows. If she hits them with Freeze Ray they’ll do a slow Purple burst attack, though Lin You’s S1 destroys them easy. Haven’t tested with multiple out at once in one spot but if there’s just one it’s nbd.
Aside from Crystal Arrow, Freeze Ray, and the Veil Follow Up Ciella’s attacks are i-frameable.
Post your thoughts and experiences with the fight below! I’m gonna try to get in for Expert in the morning.