Yup I did this map on UV-FAST because it's way too easy the normal way :) I've done it very many times so I know every secret, monsters etc. In the end I also included the cutscene which introduces you to Episode 3, even though that Episode hasn't come out yet.
The final boss (at least for now) is Eidolon. He's actually not very difficult, even on UV-FAST. He has about 7000 HP (if you think about it, that hyper-Acolyte from the previous map had like 6000 HP so it's not too much). He has 4 attacks which are: 1.) throwing a big but slow fireball at you 2.) trapping you inside a group of pikes (or whatever those are) which makes it harder for you to move around 3.) stomping on the ground, which causes fire to stream out in all 8 directions and makes some burning rocks fall down around him (the fire can also hurt himself) 4.) bending over to use a powerful firebreath which also leaves flames on the ground. he only uses this if you're close to him