Metamorphmagus

A Metamorphmagus is a witch or wizard able to change their appearance at will, with no wand, incantation or potion involved. Everyone else needs Polyjuice Potion or Human Transfiguration to manage anything comparable. The ability is rare and cannot be learned: a Metamorphmagus is born, not made, the sharpest difference from an Animagus, which anyone with skill and patience can train into. An Animagus also takes one animal form, fixed by their own nature, where a Metamorphmagus can look like almost anybody, shifting age and gender, or alter a single detail such as hair colour or the shape of a nose. The gift answers to feeling as much as intent, so appearance follows mood, and shock or grief can make it hard to use at all. Nymphadora Tonks collected detentions at Hogwarts for turning into teachers, and took full marks in Concealment and Disguise in Auror training.