Random Ghost spawn from the 2nd(the back one in the rear of the castle) Resurectionist area.
If you didn't know all the ghost models come from these areas. Killing all 4 resurectionists doesn't stop them from spawning btw. Bugged? dunno never has before tho. Anyway, he's highly MR, like the rest of the zone, and hits about 400ishmax. Casts no spells. lvl 63 is accurate. Has about 10-15k hp. Wasn't bad at all duo for a Rog/Shm combo. None of the rares are once slowed tho.