This used to be a mod, but it was later turned into a standalone game
The Dark Mod, a standalone Thief-inspired game built on the Doom 3 engine, has reached version 2.01.The Dark Mod is not a recreation of the original Thief game developed by Looking Glass Studios, it only draws its inspiration from it.
Highlights of The Dark Mod 2.01:
• Several issues surrounding combat have been corrected;
• Some graphical improvements have been implemented for the character models;
• Some technical fixes have also been added;
• An issue with TDM failing to reload missions if your folder was not named “darkmod” has been fixed;
• The player no longer takes double damage from weapons in 2.0;
• It's now harder to avoid weapons by running backwards;
• Combat has been made slightly more forgiving at lower difficulty and harder at the higher difficulties.
Check the official announcement for more details about this release. Download The Dark Mod 2.01 right now from Softpedia.