Tiberian Sun: Reborn

Description
Tiberian Sun: Reborn is a free fan-made first/third-person multiplayer shooter with strategic elements. Its code is based on a heavily modified W3D engine from the 2002 game Command & Conquer: Renegade, and replaces its units and environments with those from Tiberian Sun and its Firestorm expansion pack.
It has only a multiplayer mode, based on the default C&C mode from Renegade's multiplayer segment. Players are divided into two teams (GDI and Nod) and have to eliminate each others' bases or have the highest team score at the end of the session. Key buildings like refineries (through harvester units) bring in credits, which can be used to convert the player into a different infantry unit and/or purchase a drivable vehicle in appropriate production structures.