If you meet this guy in the fog on a full-moon night, you'd better hope to make it to the nearest tree before him. Although, never know, he just might be able to climb after you... Look well, he is no ordinary beast, but one who has the clevernes and cunning of a human. There are at least four tell-tales, if you pay attention.
This is how I see a werewolf. Not a hideously malformed mutant, but a sleek and powerful predator, disconnected from the human-self but still in full posession of his intelligence. Run for your life. (Painter7, Photoshop7, Tablet)