Nexuiz

Nexuiz is a free, cross platform, first person shooter distributed under GNU General Public License by Alientrap Software. It started back in May 31 2005 with version 1.0 using DarkPlaces, a significanlty modified quake engine. The current version, 2.2.3, was released on January 26, 2007. Nexuiz’s logo is based on the chinese character “力” which means strength.

Several notable features of the game include

ability to multiplay up to 64 players
ability to generate bots for practice sessions
dynamic lighting system similar to Doom 3