Open Source Games are a dime a dozen, I hand picked you my favorites.
Cube 2: Sauerbraten
is a free and open source game with multiplayer & singleplayer first person shooter, the successor of the Cube FPS.
Much like the original Cube, the aim of this game is fun, old school deathmatch gameplay and also to allow map/geometry editing to be done cooperatively in-game.
The engine supporting the game is entirely original in code & design, and its code is Open Source (ZLIB license, read the docs for more on how you can use the engine).
It’s an epic, all-out first-person battle so impressive, you’ll give yourself a quick pinch every time you remember it’s completely free.
There are in-game purchases of course, but you can still dive into gaming’s biggest ever battlefield and be useful with just default gear. Open Source Games are the best!
is a multiplayer online battle arena game in a three-dimensional environment, presented from an obliquehigh-angle perspective.
The player commands one of 109 controllable character “Heroes.” Each Hero begins the match at level one and becomes more powerful
by accumulating experience points through combat, thereby leveling up to the maximum level of twenty-five.
With every level gained the player either selects a new ability for their Hero to learn or enhance their general statistics.
Each Hero’s method of combat is influenced by its primary property: Strength, Agility, or Intelligence.
Path of Exile
A Diablo III-style third-person role-playing game, Path of Exile is a bit different from most free-to-play games out there.
It’s not just about whacking real life people until they scream at you in shrill pubescent tones through their Skype headsets.
TrackMania Nations Forever
The real laws of physics have little to do with the way this racer plays, but it provides more action than your average power sliding arcade racer as a result.
It’s racing meets extreme sports with an unlimited rev counter – and that’s a great combo. Great Open Source Game