Of course, the fact that this was on Cartoon Network made me think of a crossover I REALLY want to see:
HELLBOY: So we... oh, crap. I TOLD you guys what I think of psychics.
DR. ORPHEUS: I'll have you know that I am NO MERE PSYCHIC! I am *thunderclap* DR. ORPHEUS, MASTER OF NECROMANCY!!
HELLBOY: Oh, THAT'S just GREAT. Who the hell let the necromancer in here?