The DarkPlaces game engine encompasses more than 10 years of research and development in the field of real-time game engine technology by Forest "LordHavoc" Hale and Rudolf "divVerent" Polzer. Based off GPL GLQuake engine source code released by id Software, DarkPlaces Game Engine is one of the most solid and robust 3D engines available. It lets you to unleash your creative potential at virtually no cost.
The team behind Steel Storm has now setup a modding portal for the Darkplaces engine and their games. The portal is being built to fill the void of Darkplaces tutorials for modders and independent game makers alike. A mapping tutorial has been setup for users. If you're interested in modding Steel Storm or Darkplaces, check it out!