"CONSTANT VIGILANCE!"
     -- Alastor Moody, quite frequently

The best Auror the Ministry ever had. Friend of Dumbledore and the Weasleys. A bit paranoid these days, but not without reason.

"A dull clunk echoed through the Hall on his every other step. (His face) looked as though it had been carved out of weathered wood by someone who had only the vaguest idea of what human faces are supposed to look like, and was none too skilled with a chisel. Every inch of skin seemed to be scarred.  The mouth looked like a diagonal gash, and a large chunk of the nose was missing. But it was the man’s eyes that made him frightening. One of them was small, dark, and beady. The other was large, round as a coin, and a vivid, electric blue. The blue eye was moving ceaselessly, without blinking, and was rolling up, down, and from side to side, quite independently of the normal eye--and then it rolled right over, pointing into the back of the man’s head, so that all they could see was whiteness." (GF12)