Dark Dungeon I is a mod for registered Wolfenstein, made by Kenny Roels (also known as RKS Kenny). It was uploaded on the Dome on May 27, 2002 together with its sequel, though both might have been created earlier.
The mod follows an episodic flow, featuring 9 levels on Episodes 1, 2, 4 and 5. Episodes 3 and 6 features 5 and 4 levels, respectively.
Similar to Wolfenken, it features sounds only used in mods by Roels. Graphics are also taken from other games outside Wolfenstein 3D, including Doom. Other graphics originated in The Final Solution and Totengraeber.
A unique EXE is included, though the Read Me states that Roels did not make any source code changes. All files also use a different file definition, .RKS.
Certain levels suffer from having too many visible objects and the No free spots in objlist! error occurs from time to time. After Wolfenken was ported to SDL in late 2013, which fixed these issues, a Dark Dungeon port was also in the works.