[Sword of Convallaria] Weapon Trial 2 - Stage 9 (level 60) ft. Crimson Falcon

Some important notes:
Papal Guard + Gibbous tarot is very useful, and the anti heal immunity trinket can make the run more manageable.
You can replace Inanna with Samantha (she has the 3 NRG revive for the first double arrow). Also change the co op buff on inanna to single heal, I'm just lazy to restart the run and to show you that we have some room for error here.

Boss attack pattern will be:
0. Double arrow on two back units (only at the start)
1. Arrow on back unit
2. Damage on 2 front units + Cross AoE
3. AoE damage on middle 3 column
Repeat to 1.

I think level 40 is the minimum requirement to be able to 3 star this (unless you have godly gears, I tried for hours to no avail).