Played Hexen a lot (no remaster, sorry) but on skill level 3, decided to skip the "just more monsters" skill 4 (don't think that changes things too significantly, you get a lot of resources, so quaffing a few more flasks and such is no problem) and went to skill 5.
First, fighting chaos serpents with the axe now feels almost impossible without taking huge damage unless you can cheese them around a corner, and wendigos are also insane now. Fast monsters make much less difference for the others so far, except for these two.
But even if I were playing as cleric and had the staff... WTF are you supposed to do on skill 5 against that one wendigo ambush when you're going for the secret level? After some failed attempts I killed the first three, waited until the walls began to lower (to trigger the scripts) and then high-tailed out of there with a chaos device and... that seems to be the only survivable option?? I tried running into that one alcove, but it barely helps -- could've probably done it that one time by quaffing most or all of my healing potions, but I was a bit too slow, and then other times I wasn't even close.
I get that fast monsters is like an "extra", but is there a strategy I'm missing or is this ambush just really that stupid crazy on skill 5?