Anything that is out for blood is dangerous to me, so that's why I chose the vampire. I don't think it gets any worse than that.
I just looked at Dalek. pretty vicious minus its glaring eye weakness. With prep though, it changes to Predator I think.
As much as I agree that Daleks are the most conniving and utterly evil of beings out there, I had to give my vote to the Xenomorph. Dressing as one won me $50 and a chance to shake hands with Bruce Campbell at a costume contest.
considering godzilla is a giant lizard that could literally crush one of the others by accident and not know or care... that's pretty freaking dangerous to me. add in the breath and yea...
oh, question: how many of these could single-handedly destroy cities? without tech, without aid, nothing.