Digital Paint: Paintball 2 is a Paintball game that started out as a mod for quake 2 but then took on a life of its own as an open source fps game with a global player and clan management system.



Quake is described as 'Classic first-person shooter game that revolutionized the genre with its fast-paced action and innovative multiplayer modes. Originally released in 1996, it continues to be a beloved title among gamers' and is a popular first-person shooter in the games category. There are more than 50 games similar to Quake for a variety of platforms, including Windows, Linux, Mac, Steam and Playstation apps. The best Quake alternative is Xonotic, which is both free and Open Source. Other Quake like games are Half-Life, Unreal Tournament, AssaultCube and Doom.
Digital Paint: Paintball 2 is a Paintball game that started out as a mod for quake 2 but then took on a life of its own as an open source fps game with a global player and clan management system.



Wolf Team is a fast paced 3D MMOFPS that features the ability for players to transform between playing as a Human or as a Werewolf. Humans have an assortment of weapons available at their disposal giving them an advantage at a distance.
Touhou Project is a series of vertically scrolling bullet hell shooting game produced by [Oota Jun'ya (ZUN)](http://www16.big.or.




A truly free and open source multiplayer shooter, no strings attached. Have casual deathmatch matches on various scenarios. Build your own levels with the ingame editor and assets that come with the game, or just play around and use it as a sandbox.




Unvanquished is a free, open-source first-person shooter combining real-time strategy elements with a futuristic, sci-fi setting. It is available for Windows, Linux, and Mac OS X.








Fight under the onslaught of mutated monsters, obsessed soldiers and even darker bosses. Just try to survive and find out what to do next in this life, simultaneously tearing your enemies to pieces.




The website linked is not real page, just moddb page. Wikipedia says all official sites have been closed.

Take part of history’s greatest battle of Green VS. Tan. Fight amongst and against others online. Sometimes the greatest battles are fought by the smallest of soldiers.

Jake2 is a Java 3D game engine. It is a port of the GPL’d Quake2 game engine from id Software. To use the Jake2 engine you need either the data files from the original game or from the demo version that is available for download from ftp://ftp.idsoftware.com.



Dead Space is a survival horror third-person shooter video game for Microsoft Windows, PlayStation 3 and Xbox 360.




3rd Person shooter. Sure it's horror, but they can't compare.
QUAKE multiplayer is/was a big deal. Dead Space doesn't have one.