The 3 Lesser horrors were just from 3 casts. I really needed a couple of AC upgrades on my horrors, but the roll of the dice didn't go my way.
I only cast BoT after Man told me he was joining forces with you, to gang up on me once Marignon was destroyed. It's always a difficult decision what to do when one is not in a position to win. Hastening my death is not a totally terrible thing, because I really couldn't compete at blood hunting, and AC makes it tough to use the D gems income which is all I got out of taking over most of Ermor.
Your devils are going to cause havoc for my thugs, because that's what they are ... thugs, not SCs, and they need a chance to buff up before they can fight effectively. It's the paralyzing poison from the tail attack that's most worrisome. Plus all my thug gear is still undead-killing weapons -- charcoal shields and flame brands aren't the best weapons against Aby.
I'll play a few more turns and see if I can kill some devils off before I'm completely wiped out.