I've been playing around with vampires and werewolves in the world I'm creating, trying to break the cliche and come up with something interesting. So far, I've got them both as shapeshifters, "vampires" turning into mildly hunch backed, leathery skinned humanoids, while "werewolves" become hairy gorilla-like creatures with flat faces. I like that side of it, but I had another recent idea.
What if there was a third creature? Some type that made a triangle, of sorts, with the vampires and werewolves?
Now, my problem is just what it would be. Cats, dogs and the like would be too similar to werewolves in my mind, while the vampires represent lizards in my story but also bats in traditional fantasy, so that kind of cancels out any flying animals. I also figured the new race would have to be based on some kind of predator, as blood sucking bats and wolves were the inspiration for the traditional pair. I also had a suggestion recently to use an animal that's less aggresive but equally deadly when provoked (the example I was given was dolphins, who apparently can kill a shark but are obviously more docile than wolves. Not sure about that, though) that could perhaps act as judges of the other two races.
So, my question is, does anyone have any suggestions for what this third creature might be? And also, what are your thoughts on this idea in general?