Open source voxel world
Odamex is a free, cross-platform, modern client-server Doom engine
Cross-platform real-time strategy game (3D)
A free 3d game for PC that does not limit the player. Fight,Build,Gain
A fun realistic multiplayer free-and-open-source first-person-shooter!
Free MMORPG
a PHP based leaderboard software for Battlefield 4
a PHP based leaderboard software for Battlefield Hardline
Free strategy browsergame engine.
a PHP based leaderboard for World of Tanks and World of Warplanes
Free 3D Roguelike action RPG
Earthlead is a free massive multiplayer online browser strategy game.