Open source games

Games that have an open source license for engine and content.
Feel free to comment.

Armagetron Advanced

Armagetron Advanced
"A Tron clone in 3D" This has been the tagline of Armagetron, since, well, a very long time, and is probably the shortest and most...

Enigma

Enigma
Enigma is a puzzle game inspired by Oxyd on the Atari ST and Rock'n'Roll on the Amiga.

Freeciv

Freeciv
Freeciv is a Free and Open Source empire-building strategy game inspired by the history of human civilization.

Frozen Bubble

Frozen Bubble
Frozen Bubble is a game in which you throw colorful bubbles and build groups to destroy the bubbles.

Globulation 2

Globulation 2
Globulation 2 is an innovative Real-Time Strategy (RTS) game which reduces micro-management by automatically assigning tasks to units.

GLtron

GLtron
gltron was inspired by the film tron - actually, more by all the games that where inspired by the film tron :-) It's a game for one...

Gunroar

Gunroar
Gunroar is an excellent shooter in which the game environment turns to be the sea and our spaceship an armed boat.

NetHack

NetHack
NetHack is a single player dungeon exploration game that runs on a wide variety of computer systems, with a variety of graphical and...

Netrek

Netrek
Netrek is a multi-player battle simulation with a Star Trek theme.

Neverball

Neverball
Neverball is a game of skill in which your task is to tilt the floor to roll a ball through various obstacle courses, collecting coins...

Nexuiz Classic

Nexuiz Classic
Nexuiz Classic (formerly known as “Nexuiz”) is a 3D deathmatch game that has been in development since the summer of 2002.

OpenArena

OpenArena
OpenArena is a free network enabled multiplayer first person shooter based on the ioquake3 fork of the idTech 3 engine (engine of Quake III Arena).

PokerTH

PokerTH
In Texas Hold'em Poker, seven cards are available to each player.

Scorched3D

Scorched3D
Scorched3D is a game based loosely (or actually quite heavily now) on the classic DOS game Scorched Earth “The Mother Of All Games”.

SuperTux

SuperTux
SuperTux is a classic 2D jump'n'run sidescroller game in a style similar to the original Super Mario games.

SuperTuxKart

SuperTuxKart
Karts. Nitro. Action! SuperTuxKart is a 3D open-source arcade racer with a variety characters, tracks, and modes to play.

Teeworlds

Teeworlds
Teeworlds is a free online multiplayer game, available for all major operating systems.

WarMUX

WarMUX
War is declared! Have the mascots of your favorite free software titles battle it out in the Wormux arena using dynamite, grenades,...

Xonotic

Xonotic
Xonotic is a fast paced free, open-source first person shooter (arena style) licensed under the GNU General Public License.

X-Moto

X-Moto
X-Moto is a 2D-Motocross-ability-game, where physics play a significant role.

Comments

This list is not really needed. You can get all such games if you just go on “All Games” and set the license filter to “Open Source”.