Odamex is a free, cross-platform, modern client-server Doom engine
A free 3d game for PC that does not limit the player. Fight,Build,Gain
0 A.D. is a free, open-source, cross-platform real-time strategy game.
A fun realistic multiplayer free-and-open-source first-person-shooter!
Super Smash Flash 2 is the most must-play battle game with 28 classic
A collection of all maps and games made for the TripleA game engine
Java decentralized cross-platform network multiplayer game engine
Free strategy browsergame engine.
3D FPS Digital Paintball 3 Multiplayer Online Game
Library for creating turn-based games with simultaneous moves.
Action-packed local multiplayer game
Mighty 34th century meka action from TeamXbow
A Dungeons & Dragons Miniature Game.
A Co-op/Deathmatch Mod for half-life 2
Just Another Generic Shooter
Opensource serious game engine for multiplayer games