Yes, Vampire Lords. I stand corrected. Obviously I don't use them much.
They're 77 slaves and they have a dowsing bonus, so they're barely cheaper than empowering (by 3 slaves). Of course you won't spend 200+ blood slaves to empower to B3, you'll just empower to B1 and use a Ring of Sorcery + Wizardry. You're probably right that this isn't any easier than using Tartarians. Lately I've been bootstrapping up to Bloodstones but I still don't use Blood magic per se, and I feel a little bit guilty about the Bloodstones every time Bogus and his chums free the old man's daughter.
-Max