The Dark Mod

The Dark Mod is a free and open-source software first-person stealth video game, inspired by the Thief series by Looking Glass Studios. The game provides the basic framework and tools (engine, assets, models, and editor) for more than 170 fan-made missions, including several multi-mission campaigns. The Dark Mod was founded by David Massey and first released in 2009 as a total conversion mod for Doom 3. Version 2.0 was released in October 2013 as a standalone game using the open-source id Tech 4 game engine.