Fan games

OpenTTD is a business simulation game in which players try to earn money by transporting passengers, minerals and goods via road, rail, water and air. It is an open-source remake and expansion of the 1995 Chris Sawyer video game Transport Tycoon Deluxe.

StepMania is a cross-platform rhythm video game and engine. It was originally developed as a clone of Konami's arcade game series Dance Dance Revolution, and has since evolved into an extensible rhythm game engine capable of supporting a variety of rhythm-based game types. Released under the MIT License, StepMania is open-source free software.

thumb|Some penguins marching in the snow Pingus is a free software game programmed by German developer Ingo Ruhnke. It is a clone of Lemmings in which the characters are penguins instead of lemmings.

OpenArena is a free and open-source video game. It is a first-person shooter, and a fork of ioquake which in itself was a fork of Quake III Arena.

Simutrans is a cross-platform simulation game in which the player strives to run a successful transport system by constructing and managing transportation systems for passengers, mail and goods by land (rail, road, tram, monorail, maglev), air (airplanes) and water (ship) between places. Like OpenTTD, Simutrans is an open-source transportation game based on the Transport Tycoon idea.

2006 video game

Lincity is a free and open-source construction and management simulation game, which puts the player in control of managing a city's socio-economy, similar in concept to SimCity. The player can develop a city by buying appropriate buildings, services and infrastructure. Its name is both a Linux reference and a play on the title of the original city-building game, SimCity, and it was released under the GNU General Public License v2.

video game based on pre-existing media made by fans

thumb|254px|Four tribes in Widelands Build 20 thumb|254px|Screenshot of a game taken in 2008 thumb|254px|Screenshot of the "Dolomites" map in Widelands Build 19

2003 video game

2012 video game

thumb|Bos Wars|Battle of Survival screenshot Stratagus is a free and open-source cross-platform game engine used to build real-time strategy video games. Licensed under the GNU GPL-2.0-only, it is written mostly in C++ with the configuration language being Lua.

TetriNET is a multiplayer online Tetris game for up to six people that supports team play.

2010 video game

Japanese independent video games

2023 fan prequel to the video game Undertale

2013 video game

2012 adventure video game

2018 video game

2010 video game

thumb|Screenshot of OpenMW with Example Suite content

2004 video game

2010 flash video game

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