I suspect you are right and it'll work with the untransformed bat, which sucks a bit because it means I'll have to use TBT in the first round already, when I could wait to soak up some more damage.
Ironically, their transformation is also a substantial boon, because it enables them to shake off all sorts of pesky effects like burning or shock from the lightning spell.
Also, eviln is almost a non-option as in some battles (e.g. against archdemons, those damn ridiculously overpowered orcs!) the level 3 vampires barely survive into the second round, if at all. Plus with the huge armies on impossible many turns usually have to pass before there's a usable corpse.
Anyhow, playing with vampires is a lot of fun and almost as powerful as the dark knight strategy. And I have no special vampire/undead gear or skills at all!
