Aaaaand I've finished it again without much issue.
It's a little more tedious and I do like the challenge of being unable to open the menu whilst fighting (really makes planning ahead or having Blue and Red Pots on hand paramount!), but I didn't find it anymore difficult than if you were in HARD mode aside from enemies being disillusioned a little faster.
That said, yeahhhh, not saying Succubus Lona is the end all be all- I'd be fucked if it were against the
. Of course, getting outnumbered and cornered is always a bad time.
But is it borderline unplayable, or one of the most difficult builds to play? Nah.
Note: When I say "finished," I mean "killed/juiced everything"