Super Tux Kart
Name: SuperTuxKart
Similarity: Crash Team Racing
Genre: 3D racing
Multiplayer: yes
Similarity: Super Mario Bros
Genre: 2D side-scrolling adventure
Multiplayer: no
Availability: Deb
License: free software, free data
Website: https://www.supertux.org
0 A. D.
Name: 0 A. D.
Similarity: Age of Empires III
Genre: Real Time Strategy (RTS)
Multiplayer: yes
Availability: deb, snap
License: free software, free data
Website: https://play0ad.com
Similarity: Doom II
Genre: First Person Shooter (FPS)
Multiplayer: yes
Availability: Deb, Snap
License: free software, free data
Website: prboom-plus.sourceforge.io, freedoom.github.io
Doom III
Description: Dhewm3 is a free software version of the world-rocking FPS of its own age (was competing with Half Life 2 at that time) Doom III. Unfortunately, it requires you to have the original Doom CD/DVD in order to use the proprietary data and we don’t know of any way it can play with a free data. In other words, it has not yet reached the stage Doom II already did.
Similarity: Doom III
Genre: FPS
Multiplayer: yes
Availability: Deb
License: free software, no free data
Website: https://dhewm3.org
Frozen Bubble
Name: Frozen Bubble
Similarity: Puzzle Bobble
Genre: kids arcade
Multiplayer: yes
Availability: Deb
FlightGear
Name: FlightGear
Description: realistic 3D aircraft, helicopter flight simulator. This game can take you flying freely with beautiful scenery.
Similarity: Microsoft Flight Simulator
Genre: flight simulator
Multiplayer: yes
Availability: Deb, Snap
License: free software, free data
Website: www.flightgear.org
Warzone 2100
Name: Warzone
Description: futuristic 3D real time strategy, battle against colonies of robots and alients.
Similarity: Starcraft
Genre: RTS
Multiplayer: yes
Availability: Deb, Snap
License: free software, free data
Website: https://wz2100.net
Chromium BSU
Name: Chromium BSU
Description: Chromium BSU (not to be confused with Chromium Browser) is an arcade 2D aircraft shooting adventure.
Similarity: a lot of arcade aircraft shooting games
Genre: arcade aircraft
Multiplayer: no
Availability: Deb
License: free software, free data
Website: chromium-bsu.sourceforge.io
OpenRA
Name: OpenRA
Similarity: Command Conquer, Red Alert, Tiberian Dawn, Dune 2000
Genre: RTS
Multiplayer: yes
Availability: AppImage
License: free software, no free data
Website: https://www.openra.net
OpenTTD
Name: OpenTTD
Description: OpenTTD is a free software version of popular city (transportation) building Transport Tycoon Deluxe. You are a mayor and you should build your city transportation as good as possible.
Similarity: Transport Tycoon Deluxe
Genre: city simulation
Multiplayer: no
Availability: Deb
License: free software, free data
Website: www.openttd.org
OpenSA
Name: OpenSA
Description: created with the same engine software as OpenRA, OpenSA is an RTS game of war between insects like ants, spiders etc. using bazooka and other guns in a swarm. It’s name is a pointer that it is a free software version of an old, abandoned proprietary game called Swarm Assault.
Similarity: Swarm Assault
Genre: RTS
Multiplayer:
Availability: AppImage
License: free software, no free data
Website: www.moddb.com/mods/opensa
Swell Foop
Name: Swell Foop
Description: this is a colorful same game from GNOME. You can play this to get rid some free time, or play colors with kids. It's officially available on Ubuntu.
Similarity: Same Game
Genre: kids, puzzle game
Multiplayer: no
Availability: deb
License: free software, free data
Website: wiki.gnome.org/Apps/Swell%20Foop
TORCS
Name: TORCS
Description: The Open Racing Car Simulator (TORCS) invites you to play 3D car racing games. It's available officially on Ubuntu.
Similarity: Need For Speed
Genre: 3D car racing
Multiplayer: yes
Availability: Deb
License: free software, free data
Website: https://torcs.sourceforge.net
Tux Math
Name: Tux Math
Description: TuxMath (tuxmath) is an educational game for kids learning their math. It can be played either alone or together, for kids from age of Elementary Student to even High School ones. Questions will fall from the above slowly and the kid should answer it, for example, 1 + 1 = ?, until all of them finished. The more your kids play it, the more they will be better in math.
Similarity: -
Genre: education
Multiplayer: yes
Availability: Deb, Snap
License: free software, free data
Website: https://sourceforge.net/projects/tuxmath
Tux Typing
Name: Tux Typing
Similarity: -
Genre: education
Multiplayer: no
Availability: deb
License: free software, free data
Website: https://sourceforge.net/projects/tuxtype
Tux Paint
Similarity: -
Genre: education
Multiplayer: no
Availability: deb
License: free software, free data
Website: https://tuxpaint.org
Red Eclipse
Name: Red Eclipse
Similarity: Counter Strike, Xonotic
Genre: FPS
Multiplayer: yes
Availability: Deb, Snap
License: free software, free data
Website: www.redeclipse.net
(Tesseract game engine video from YouTube)
Speed Dreams
Name: Speed Dreams
Description: a 3D sport car racing game.
Similarity: Need For Speed, TORCS
Genre: 3D car racing
Multiplayer: yes
Availability: AppImage
License: free software, free data
Website: www.speed-dreams.net/en
Xonotic
Name: Xonotic
Similarity: Counter Strike, Xonotic
Genre: FPS
Multiplayer: yes, with offline mode available
Availability: Deb, Snap
License: free software, free data
Website: https://xonotic.org
Zaz
Similarity: Zuma, Luxor
Genre: 2D marble shooting
Multiplayer: no
Availability: Deb
License: free software, free data
Website: https://zaz.sourceforge.net
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Worth Mentioning
We would love to introduce free software to make video games (called "game engines") with visual editor available on Ubuntu repository (or at least on GNU/Linux in general) which you can use to produce both commercial and hobbyist games:
Godot, a 2D/3D drag-and-drop and coding based game engine.
GDevelop, a 2D/3D drag-and-drop without coding based game engine. *
Solarus, an action RPG maker famous for its game series Zelda.
LOVE2D, a Lua scripting based game engine. No visual editor.
EasyRPG, a free software community version of RPG Maker. Still in early development. *
Ikemen-GO, a coding-based fighting game engine compatible to MUGEN assets capable to make games like Street Fighters or Samurai Showdown. No visual editor.
Open 3D Engine (O3DE), a full-featured game engine with advanced visual editor. *
Stride, a C# and .NET based 3D game engine with advanced visual editor.
*) Not available on Ubuntu repositories yet but available to download from its home page.
See Also
Finally, we would love to introduce emulators already available on Ubuntu (or GNU/Linux in general) to play games you found only on other platforms e.g. arcade and game consoles. This means Ubuntu can play your favorite PlayStation, Xbox, Nintendo, SEGA, GBA, MS-DOS etc. by using them.
RetroArch, an emulator for all video games including Arcade and Game Boy Advance.
Ares, an emulator for all video games including Atari and SEGA.
Desmume, en emulator for Nintendo DS.
PCSXR, an emulator for Sony PlayStation 1.
PCSX2, an emulator for Sony PlayStation 2.
Xemu, an emulator for Microsoft Xbox.
WINE, an emulator for Windows games.
Dosbox-X, an emulator for MS-DOS games (based on Dosbox).
References
1. What is free software? The definition by GNU Project.
2. List of Game Engines by GitHub
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