Parasite universe

Discworld, the fictional planet of a fantasy series by Terry Pratchett, exists at a point near the very edge of universe's reality spectrum. From here, the fabric of the fictional universe's reality is gossamer-thin, and excessive pushing can and often does break holes into other, often far less hospitable, domains. The most dangerous of these domains are the Dungeon Dimensions, a region beyond the narrative's reality itself, whose inhabitants (inspired by the formless horrors of H. P. Lovecraft) wait to swamp our reality with all the force "of an ocean warming itself against a candle". A number of minor fictional universes attach themselves tangentially to the Discworld universe, particularly List of dimensions of the Discworld#Death's Domain, the home of the Disc's Grim Reaper, from which he descends to do his job, and the parasite universe of Fairyland, home of the sociopathic and vicious Elves. Additionally, the Dark Desert is a region that, according to the Discworld's Omnian religion, souls cross to pass into the next world. The Discworld character Death frequently takes souls here, and in recent books, it seems to have become the afterlife of choice for most Discworld characters, not just Omnians.

Pratchett has also established a version of Hell, similar to that described by Dante, (though rather than "Abandon All Hope, Ye Who Enter Here", the sign above its gates reads "You Don't Have To Be Damned To Work Here, But It Helps!!!") and, like Milton's Hell, its capital is Pandaemonium. Various other Underworlds have also been documented, similar to Hades or Annwn. Another universe connected to the Disc is Roundworld (our own universe), initially created, from an in-universe perspective, by the wizards of the Unseen University as a zone where the laws of magic did not apply. A final Pratchett-created dimension is L-space, a dimension that connects every library and book depository in the universe. L-Space is portrayed as a natural outgrowth of the fact that "knowledge=power=energy=matter=mass" and mass warps space, and therefore, libraries in the Discworld universe are a very dangerous place indeed for the unprepared.

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