Shadowtravel

Shadowtravel is a form of non-conventional magical travel utilized by creatures from the Undershadow, as well as magic users inclined to the Dark Arts.

When a creature shadowtravels, they appear to step into one shadow and out of another. However, for the creature doing the traveling, they actually step into the Undershadow. Time does not flow for the creature while it remains there, and it can move to the point it wants to reenter the Overworld, at which point it steps back through the shadows into reality.