Here we present 30 Free Open Source Games that you must try at least once.
Please contribute to these Open Source games either as a user by installing and testing them or as a developer by contributing to the open source code. You could also contribute by making a donation via their websites.
1. Alien Invasion
Alien Invasion is a free game, licensed under GNU GPL, heavily inspired by the X-COM series by Mythos and Microprose. It is is a strategy game featuring tactical combat against hostile alien forces which are about to infiltrate earth at this very moment. You are in command of a small special unit which has been founded to face the alien strike force. To be successful on the long run, you will also have to have a research team study the aliens and their technologies in order to learn as much as possible about their technology, their goals and the aliens themselves.
Operating System: Windows, Mac, and Linux
Download the source here.
2. Alien Arena
The goal of Alien Arena is to create the perfect marriage between Quake and Unreal Tournament, between retro sci-fi and futuristic tech, and between casual gamer and advanced expert, and wrap it up in a package with quality that could rival that of commercial games. Alien Arena claims to have one of the most active, loyal, and committed communities of any free game in existence.
Operating System: Windows, Linux, Ma OS X
Download it here.
3. Armagetron Advanced
Armagetron a free open source software multiplayer game in 3d that attempts to emulate and expand on the lightcycle sequence from the movie Tron. It’s an old school arcade game slung into the 21st century. Highlights include a customizable playing arena, HUD, unique graphics, and AI bots.
Operating System: Windows, Linus, Ma OS X and BSD
Download the software here.
4. AssaultCube
AssaultCube was formerly known as ActionCube It is a free first-person-shooter game that is based on the game Cube. It provides a realistic looking environment while gameplay stays fast and arcade. This game is all about team oriented multiplayer fun.
Supported Operating Systems: 64-bit MS Windows, All 32-bit MS Windows (95/98/NT/2000/XP), All POSIX (Linux/BSD/UNIX-like OSes), OS Portable (Source code to work with many OS platforms), Linux, OS X, Vista, Win2K, WinXP, Microsoft Windows Server 2003.
5. Bzflag
Bzflag is a open source OpenGL multiplayer battle zone capture the flag game. Its a 3D first person tank simulation game.
Operating System: Windows, Linux,
Mac OS X
Download it here.
6. Blender Breakout
Blender breakout is a simple open source game much like super breakout. it is developed in Blender
Operating System: Windows XP
Download the game here.
7. Blood Frontier
The game is a single-player and multi-player first-person shooter, built as a total conversion of Cube Engine 2, which lends itself toward a balanced gameplay, completely at the control of map makers, while maintaining a general theme of tactics and low gravity.
Operating System: Windows, Linux/BSD and Mac OSX. The source code is OP portable.
Download the software here.
Commander Stalin is a Soviet real time strategy game (RTS) based on Boswars. In a RTS game, the player has to combat its enemies while running his war economy. Its so called real-time, as opposed to turn based games where the player always has to wait for his turn. The trick is to balance the effort put into building the economy and building and army to defend an attack the enemies
Operating System : Windows, Linux
9. Complete Annihilation
Complete Annihilation is a game for the Spring RTS engine. It traces its heritage to Total Annihilation (often referred to as Original Total Annihilation or OTA), a 1997 PC RTS by Cavedog Entertainment. However, CA is not OTA. It is gradually moving away from OTA, replacing the copyrighted models and textures with open-source ones while refining and improving the gameplay. CA aims to be a dynamic, action-packed, hassle-free game, full of clever strategies and constantly moving combat.
Operating System: Linux
The procedure for download can be found in this site
10. Cube
Cube is an open source multiplayer and single player first person shooter game built on an entirely new and very unconventional engine. Cube is a landscape-style engine that pretends to be an indoor FPS engine. It combines very high precision dynamic occlusion culling with a form of geometric mipmapping.It Uses OpenGL & SDL.
Operating System: Officially supported platforms (client & server) are win32, Linux & bsd (x86), Mac OS X (ppc) and Pocket PC (xscale), and includes source code (open source: ZLIB license)
Download the game here
Cube 2: Sauerbraten is a free open soure multiplayer / single player first person shooter, built as a major redesign of the Cube FPS.
Much like the original Cube, the aim of this game is not necessarily to produce the most features & eyecandy possible, but rather to allow map/geometry editing to be done dynamically in-game, to create fun gameplay and an elegant engine.
Operating System: Windows, Linux, Ma OS X
12. Freeiv
Freeciv is a Free and Open Source empire-building strategy game inspired by the history of human civilization. The game commences in prehistory and your mission is to lead your tribe from the stone age to the space age. Its a turn-based multiplayer strategy game, in which each player becomes the leader of a civilization, fighting to obtain the ultimate goal “ To become the greatest civilization”.
Operating System: Windows, Linux and Mac OS X
Download the software here.
13. FlightGear
FlightGear Flight Simulator is free open source matured, sophisticated, open-source flight simulator software package, created and maintained entirely by volunteers. The goals of the FlightGear project include creating a sophisticated flight simulator framework for use in research or academic environments, for the development and pursuit of other interesting flight simulation ideas, and as an end-user application.
Operating System: Windows, Mac, Linux, Solaris and IRIX
14. Fight Win Prevail
Fight Win Prevail (or FWP for short) is a free open source multiplayer first person shooter.
The game is set in an imaginary universe where fearless pilots fight to the death with their futuristic vehicles. Gameplay lies somewhere between the Mechwarrior-series and Quake 3. It is faster and more action-orientated than in Mechwarrior, but tries to avoid the ‘jump-around-like-crazy-and-fire-at-everything-that-moves’-gameplay known from Quake 3.
Fight Win Prevail is a pure multiplayer game and does not have a real singleplayer mode. Primary target are LANs, but the game is playable over the internet, too.
Operating System: Windows, Linux
Download the software here.
15. FreeDoom
Its a free open source Doom game powered by Doom Engine. In FreeDoom, a Doom WAD file is used instead of the copyrighted file from the original Doom and Doom II.
Operating System: GNU/Linux, BSD, Mac OS X, other POSIX, Windows
Download it here.
16. Glest
Glest is a free 3D real-time strategy game, where you control the armies of two different factions: Tech, which is mainly composed of warriors and mechanical devices, and Magic, that prefers mages and summoned creatures in the battlefield.
Operating system: Linux, Windows 2000/XP. Source code is OS Portable
Download the game here.
17. Marathon
Marathon is a science fiction first-person shooter computer game published and developed by Bungie Software. It is released as freeware and the code is available under GNU GPL.
Operating System: Originally developed for MAC but ported to Mac OS X, Windows, Linux and BSD
Download the software here.
18. Nexuiz
Nexuiz is a free open source first person shooter game. Nexuiz is a fast paced 3d deathmatch game project created online by a team of developers called Alientrap.
Operating System: Windows, Mac, and Linux
Download the software here.
19. OpenRock Curling
OpenRock Curling is a free curling game with network support. It is written in Java and should run all platforms with JRE 6 or later.
Operating system: OS Independent as its written in Java
Download the game here.
20. OpenArena
OpenArena is a Free Open content package for the id tech3 GPL source code package. OpenArena is a violent, sexy, multiplayer first person shooter based on the ioquake3 fork of the id tech 3 engine. It has many game types beyond deathmatch and a lot of characters. Due to violent and racy content, it may not be suitable for children under 17.
Operating System: Linux, Mac OS X, Windows
21. PokerTH
PokerTH is a poker game written in C++/QT4. You can play the popular “Texas Hold’em” poker variant against up to six computer-opponents or play network games with people all over the world.
Operating system: All 32-bit MS Windows (95/98/NT/2000/XP), Linux, OS X
22. Rigs of Rods
Rigs of Rods is a 3D simulator game where you can drive, fly and sail various vehicles using an accurate and unique soft-body physics engine.
Operating system: Windows. Its source code is OS portable
23. SuperTuxKart
SuperTuxKart is a a kart racing game featuring Tux and friends. It is a fun-racer game, focusing on fun and ease of play. Great for both children and adults.
Operating system: Windows (XP/Vista) , Linux and Mac OSX. The source code is OS Portable.
You can download the game here.
24. Strings on Speed
Strings on Speed is a music video game similar to Frets on Fire in which players simulate guitar play using their keyboard. It features a single player as well as a multiplayer mode. Read more here
Operating system: 32-bit MS Windows (NT/2000/XP), Linux, Vista
Download the software here.
25 .Scorched 3D
Scorched 3D is a simple turn-based artillery game that is free and open source. It is also a real-time strategy game in which players can counter each others’ weapons with other creative accessories, shields and tactics. Scorched 3D incorporates a lively three dimensional landscape that includes animated jets, naval vessels, water, and even birds, in addition to detailed tanks and projectiles. Scorched 3D is actually a modernization of the classic DOS game Scorched Earth “The Mother Of All Games” on which it is based.. One can play over LAN and internet play.
Operating System: Microsoft windows (2K, Me, XP, 98, 95), Linux (Redhat, Mandrake, etc.), Mac OS X (ppc >= 10.4), Gentoo Linux and Debian Linux (Ubuntu)
Download the software here.
26. Torcs-NG
TORCS-NG is a fork of the famous racing car simulator TORCS, aiming to implement exciting new features, cars, tracks and AI opponents to make a more enjoyable game.
Operating system: 32-bit MS Windows (NT/2000/XP), All POSIX (Linux/BSD/UNIX-like OSes)
Download the software here.
27. The Battle for Wesnoth
The Battle for Wesnoth is a free open source turn-based strategy game with a fantasy theme. You build up a great army by gradually turning raw recruits into hardened veterans. Later in the game, you recall your toughest warriors and form a deadly host against whom no one can stand! Choose the units from a large pool of specialists, and hand-pick a force with the right strengths to fight well on different terrains against all types of opposition.
The world of Wesnoth is very huge and limited only by your creativity. You can make your own custom units, compose your own maps, and write your own scenarios. You can also challenge up to 8 friends - or strangers - and fight in epic multi-player fantasy battles.
Operating System: GNU/Linux, Windows, MacOSX, RISC OS, BeOS, Solaris, FreeBSD, OpenBSD, NetBSD, DragonFly BSD, AmigaOS4, OS/2 & eComStation compatible
Download it here.
28. Tremulous
Tremulous is a free, open source game that blends a team based first person shooter with elements of a real time strategy. Players can choose from 2 unique races i.e aliens and humans. Players on both teams are able to build working structures in-game like a real time strategy. These structures provide many functions, the most important being spawning. The designated builders must ensure there are spawn structures or other players will not be able to rejoin the game after death. Other structures provide automated base defense (to some degree), healing functions and much more…
Player advancement is different depending on which team you are on. As a human, players are rewarded with credits for each alien kill. These credits may be used to purchase new weapons and upgrades from the “Armoury”. The alien team advances quite differently. Upon killing a human foe, the alien is able to evolve into a new class. The more kills gained the more powerful the classes available.
The overall objective behind Tremulous is to eliminate the opposing team. This is achieved by not only killing the opposing players but also removing their ability to respawn by destroying their spawn structures.
Operating System: Windows, Linux
Download the files here.
29. UltraStar Deluxe
UltraStar Delus is a karaoke game inspired by the Singstar game available on the Playstation. It allows up to six players to sing along with music using microphones in order to score points, depending on the pitch of the voice and the rhythm of singing.
Operating System: All 32-bit MS Windows (95/98/NT/2000/XP), All BSD Platforms (FreeBSD/NetBSD/OpenBSD/Apple Mac OS X), Linux, OS X
Download the software here.
30. War§ow
War§ow is one of the best open source first-person shooter game designed to play online. There are many many games that were inspired by War§ow but still War§ow has been very unique. The Gameplay focused on speed, trick jumps and the art of movement.
Operating System: Windows, Linux and Mac
Download the game here.
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