Netherworld is a portrayal of the Fear of Disorientation, as seen in Horsemen. It is a vast alternate world with purple skies and black clouds, and is home to some of the most dangerous beings in the universe, including the Four Horsemen of the Apocalypse and The Terrorspawn. The most notable way into Netherworld are Doors, but some beings have other methods of entering it.
- The Mountain of Madness: A mountain in Netherworld, higher than any mountain that can be found on Earth, which is covered in sharp rocks and high cliffs. Only the most powerful beings dare to travel there.
- The Capital City: The capital city of Netherworld. Its name is currently unknown.
- The Red Forest: A large forest where all the leaves are red.
- The Cliffs of Suffering: A series of incredibly high cliffs.
- The Board: A portion of Netherworld owned by The Gambler. It has a checkered ground and chess piece shaped buildings.
- The Hated Palace: A mysterious palace. 12 years ago, Lord Strain stole five weapons of power from it, but dropped one of them, which was pulled through a Door into the human world.