Transformation Magic is a type of magic that Witches possess.
By using Transformation Magic, a Witch is able to alter his/her appearance. By doing this, Witches are able to travel large distances in the Human World undetected as well as follow a group or person without drawing attention to themselves.
Witches can also use Transformation Magic for partial transformations. This way, they can gain attributes that can help them in battle; Ruby gained three pairs of wings which, according to Kurumu, were equipped with blades.