The how that works still make me scratch my head since that means you are completely changing the properties of what a shadow is (the absence of light over a certain area due to an object blocking the light) and turn into some sort of.. phasing.. thing...
Absence of light= the absence of matter? Does the shadow become a sort of black hole?
I don't quite understand it myself. xD I guess they become a black hole but the thing is that the person using such magic can somehow reappear the person or themselves some place else which makes it hard to understand how it works.