I'm in dire need of help to beat the Master Challenge. I am currently running (all fully leveled and 40mc, except 45 on Hilde):
Sazanka as main, with 4.3.4 axe, MUB and leveled Juggernaut, MUB and leveled event print
Nefaria with 5.2.4 bow, level 65 Juggernaut, MUB One with the Shadows 4*WP
Hildegarde with 5.3.0 Void Light Staff, MUB leveled Unicorn, MUB leveled As the snow falls 4*WP
Cleo with 5.2.4 Staff, lv 40 Silke, MUB leveled As the snow falls 4*WP
Also, my shadow alters are 22/22, Library is 23, and my weapon facilities are all between 10-15 except for staff and bow, which are 16.
As you can see, I'm doing my utmost to keep the healers alive (last recovery prints) so they can keep Sazanka and Nefaria alive, but they struggle once the boss goes into overdrive, and eventually die to the mobs. I have the worst luck with sleep force strikes as well, and only once managed to survive (alone) to break him, but didn't have enough DPS to finish the job.
In the wings, I have Botan (70/40mc) and possibly Verica (80/45mc) waiting to swap in, but I've tried a few combinations, which didn't go over as well as the current one.
Any analysis or suggestions, even in broad strokes, would be greatly appreciated!
Edit: I've subbed Verica in for Cleo, and things are going a little bit better. Still need more DPS to finish before time up though. I'm giving lots of thought to making Sazanka my second promoted 5*...