Wundergrund
Wundergrund is a dark, twisted inner-dimension within Planet Earth. It is a glitch and the first of its kind but unfortunately not the last. Created after a horrible event caused by a Weaver called the Dissenter, it is the undead remnant of the planet, Pangaea, the first incarnate of Earth. There are exactly seventeen inhabitants of the world, thirteen of which are very powerful Errors, and one in particular has merged with a Weaver, the Dissenter itself. Any other seeming inhabitants are mocking, haunting, and warped illusions of those who once lived there, repeating in an endless cycle of repetitive motions.
When used in a mocking, depraved manner by The Thirteen, it is called Wonderland. This term is familiar to those of Earth by way of the creature Jank who told the author Lewis Carroll the amended story of a girl named Alice Liddell, a victim of their voracious appetite for the hearts, minds, and essences of living folk—particularly human children.
The Thirteen absolutely despise it when the dimension is called Wonderland.
The Thirteen
The Thirteen is an epithet given to the thirteen damned individuals that lived on after the destruction of Pangaea—or, rather, live in a state of unlife. Unable to die, unable to live properly, and not at all sane in mind, they are joined by four servants who they have willed from Wundergrund to follow them to the living world.
Alice in Wonderland
Alice's Adventures in Wonderland and Alice Through the Looking Glass, the two stories written by the Aboveground English author Lewis Carroll, were actually inspired by stories told to him by the creature Jank, a member of The Thirteen.
Jank told Carroll an amended, "safe" version of the story of their most enjoyable victim, Alice Liddell, in a sort of twisted joke of the torture the girl went through when they killed her.