"A dark vortex created by the witch or wizard can be positioned anywhere, but it takes the great power of two wizards to conjure it. It creates a gateway to anywhere in the world, transporting that witch or wizard to the place of their choice. This type of magic taps into the darkest of the magic as it disrupts the orderly manner of the surroundings the witch or wizard is in. Most wizards created this vortex as a means to escape walls of impenetrable forces such as Azkaban prison."