Alastor "Mad-Eye" Moody is perhaps the most famous Auror in the modern times of the Wizarding World, single-handedly responsible for capturing numerous wizard criminals. He is also said never to have killed his quarry, even when permitted to do so, unless he had no other choice. Moody's face is badly scarred; he has lost several body parts while fighting Dark wizards, including his left eye, lower left leg, and part of his nose; and he is cautious – some characters might say paranoid – in that he refuses to eat or drink anything which he himself did not prepare. He has replaced his missing eye with a magical one that can rotate 360 degrees and see through almost everything (including walls, doors, Invisibility Cloaks, and the back of his own head). He walks with a pronounced limp due to his prosthetic leg and uses a walking staff. He frequently exclaims "Constant vigilance!" to encourage wizards to be on their guard against the dark arts, and keeps a number of devices in his office to alert him to the presence of potential enemies. Before his retirement from the Aurors' Office, he was Nymphadora Tonks' mentor, and still regards her as his protégée.