The Nightmare, which is in Pokémon Mystery Dungeon: Explorers of Time, Explorers of Darkness, and Explorers of the Sky, is the dungeon you go in to save Azurill from him nightmare, caused by Darkrai.
To get to this Dungeon, you must get Drowzee from Mt. Travail. The Nightmare has 17 floors, ranging from B1 to B17. The Pokémon you find in this Dungeon randomly appear on one of the floors. The types are a mixture, most Normal or Water.
None of the Pokémon found in this Dungeon can be recruited, nor can this Dungeon be revisited after it is completed.
 Pokémon Encountered (Random Locations)
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