Nexuiz is geen Quake. Van de Nexuiz website:
Nexuiz is based on the Darkplaces engine, built on OpenGL technology. The darkplaces engine is an advanced Quake1 based engine developed mainly by Forest "LordHavoc" Hale, who has been working with the Quake1 engine for many years. A few of Darkplaces main features are Quake3bsp support, realtime lighting and shadowing, new particle effects, advanced menu system, and Md3 model support.