The Nightmare Castle is the stronghold of the demonic Nightmare King, featured as the territory of the Nightmare Land and one of the central locations of the Japanese/American animated film, Little Nemo: Adventures in Slumberland. A dreaded and towering, mountainous palace, containing a prison cell, which the Nightmare King holds his captives as new prisoners, the Nightmare Castle briefly appears in Disney vs. Non-Disney Villains War, being featured at the moment when the Nightmare King perishes at the hands of Chernabog. It also appears as one of the minor locations of the Non-Disney Villains Tournament, serving as the home of the demon lord.