[@Ebonsquire]

Humanoid, obviously. I'm thinking of have them evolve/breed out of their original form, only retaining a few of things left over. Which will be mainly claws, fangs, maybe wings? Still dithering over that one; anyway, these things will only come out when they want it to - like the Wendigo.
Going to do something with riddles too. Can't have a Sphinx without riddles. XD