You know what? I have an idea I want to use. I'm in after all. 

[hider=Idea] Skin changer, has kind of a werewolf vibe where the extent of their abilities depends on the phase of the moon. The fuller the moon, the more traits of whatever their chosen form they can take on. At a full moon they can transform completely, and at the new moon they shed all traits that they have taken on and return to their original form. Can mix and match traits(venom from a snake, wings of a bird, claws of a cat) and even take on another human's form. 

Price: consuming a portion of the creature in question. Usually drinking the blood. 
Other than on the new moon, the only way to shed the adopted traits is to drink healthy human blood.[/hider]