The Darkening

The Darkening Episode 1: The Nameless Project is a megawad for Doom II that contains twenty-two maps, split equally between single and multiplayer. It was released on January 7, 1999. A sequel, The Darkening Episode 2, was released the following year.

Levels
Singleplayer
 * MAP01: Scary
 * MAP02: Bloody Hell
 * MAP03: Entropia
 * MAP04: Relentless
 * MAP05: Hand of Doom
 * MAP06: The Mines of Death
 * MAP07: Dead Simple 2
 * MAP08: Discordia
 * MAP09: Military Complex
 * MAP10: Under Earth
 * MAP11: Stone Tyrant

Multiplayer
 * MAP12: The Spine of Evil
 * MAP13: Devil's Dungeon
 * MAP14: Fragmentation/Quake DM
 * MAP15: Relentless until death
 * MAP16: Sulphur
 * MAP17: Return to the Realms
 * MAP18: Valley of the Lost
 * MAP19: Vertigo
 * MAP20: Interrogation Central
 * MAP21: Death awaits 6-feet Under Earth
 * MAP22: Stone Tyrant