Cloned Games

Free & Open Source Sci-Fi Games

489 free, open-source sci-fi games — real clones and remakes you can download, inspect the source of, and modify.

Sporadic
Robot War Engine screenshot
Robot War Engine

Clone of Total Annihilation

An open-source RTS engine highly compatible with Total Annihilation's original data files.
Platforms:Windows
Stars123
Updated6 months ago
LicenseGPL-3.0
Release2017
Genre: Real-Time Strategy
Theme: Sci-Fi
Halted
Even the Ocean screenshot
Even the Ocean

Clone of Even the Ocean

Even the Ocean is Analgesic Productions' open-source narrative platformer about balancing Light and Dark energy to save Whiteforge City.
Platforms:WindowsOSX
Stars117
Updated2 years ago
LicenseUnknown
Release2023
Genre: Action
Theme: Fantasy
Active
Prey 2006: A Talon Brave Game screenshot
Prey 2006: A Talon Brave Game

Clone of Prey

A community source-port integration of Prey (2006)'s SDK with the open-source Doom 3 GPL engine; still visually unfinished.
Platforms:WindowsLinux
Stars116
Updated23 days ago
LicenseUnknown
Release2024
Genre: FPS
Theme: Sci-Fi
Active
No preview
Yamagi Quake II Remaster

Clone of Quake 2

An experimental Yamagi Quake II fork adding Nightdive's Quake II remaster support and other id Tech-era game formats.
Platforms:WindowsLinuxOSX
Stars113
Updated11 days ago
LicenseUnknown
Release2023
Genre: FPS
Theme: Sci-Fi
Active
The Ur-Quan Masters HD MegaMod screenshot
The Ur-Quan Masters HD MegaMod

Clone of Star Control 2

A fork of The Ur-Quan Masters HD-mod for Star Control II, adding many extra graphics options and QoL improvements.
Platforms:WindowsLinux
Stars111
Updated12 days ago
LicenseGPL-2.0
Release2019
Genre: Adventure
Theme: Sci-Fi
Halted
Gorc screenshot
Gorc

Clone of Star Wars Jedi Knight: Dark Forces II

Gorc is an early-development open-source recreation of the Jedi Knight: Dark Forces II engine, aiming to run its levels on new platforms.
Platforms:None
Stars110
Updated5 years ago
LicenseApache-2.0
Release2013
Genre: Fighting
Theme: Fantasy
Halted
Word War vi screenshot
Word War vi

Clone of Defender

An open-source shooter in the spirit of Defender, built with PortAudio and libvorbisfile for Linux, macOS, and Windows.
Platforms:Linux
Stars109
Updated1 year ago
LicenseUnknown
Release2012
Genre: Arcade
Theme: Sci-Fi
Halted
No preview
GloomAmiga

Clone of Gloom

The official source code for Gloom, an Amiga first-person shooter by Black Magic, released as-is with no completeness guarantee.
Platforms:Amiga
Stars104
Updated9 years ago
LicenseUnknown
Release2017
Genre: FPS
Theme: Sci-Fi
Sporadic
Nanosaur II: Hatchling screenshot
Nanosaur II: Hatchling

Clone of Nanosaur 2

Pangea's 2004 Mac game Nanosaur II, ported with permission to modern macOS, Windows and Linux.
Platforms:WindowsLinuxOSX
Stars103
Updated3 months ago
LicenseUnknown
Release2022
Genre: TPS
Theme: Prehistoric
Active
Free Allegiance screenshot
Free Allegiance

Clone of Allegiance

Free Allegiance is an open-source project built with Visual Studio and DirectX, split into client, server, lobby, and logic components.
Platforms:Windows
Stars102
Updated13 days ago
LicenseMIT
Release2017
Genre: Action
Theme: Sci-Fi
Active
EDGE-Classic screenshot
EDGE-Classic

Clone of Doom

A Doom source port reviving the older EDGE 1.35 engine with modern visuals, easy modding, and support for Heretic and other IWADs.
Platforms:Windows
Stars101
Updated25 days ago
LicenseGPL-3.0
Release2021
Genre: FPS
Theme: Sci-Fi
Active
lithtech screenshot
lithtech

Clone of The Operative: No One Lives Forever

An in-progress cross-platform source port built on the GPL LithTech engine, currently building the engine and No One Lives Forever 2.
Platforms:WindowsLinux
Stars101
Updated2 months ago
LicenseUnknown
Release2017
Genre: FPS
Theme: Comedy
Halted
No preview
64doom

Clone of Doom

A port of Doom to the Nintendo 64 via the libdragon toolchain, built from id Software's original source release; now marked halted.
Platforms:N64
Stars98
Updated2 years ago
LicenseUnknown
Release2015
Genre: FPS
Theme: Sci-Fi
Archived
No preview
Descent II

Clone of Descent II

Parallax Software's original 1999 Descent II source release, missing third-party code so it won't compile as-is.
Platforms:Windows
Stars94
Updated14 years ago
LicenseUnknown
Release2012
Genre: FPS
Theme: Sci-Fi
Halted
OpenNotrium screenshot
OpenNotrium

Clone of Notrium

An open-source SDL2 port of Ville Mönkkönen's top-down survival game Notrium for Linux, macOS, Windows and FreeBSD.
Platforms:WindowsLinuxOSX
Stars94
Updated4 years ago
LicenseUnknown
Release2014
Genre: Action
Theme: Sci-Fi
Halted
No preview
FQuake3

Clone of Quake 3

FQuake3 was an attempted F# implementation of Quake III Arena for 32-bit Windows, discontinued before reaching a playable state.
Platforms:Windows
Stars90
Updated11 years ago
LicenseGPL-2.0
Release2013
Genre: FPS
Theme: Sci-Fi
Active
No preview
three-descent

Clone of Descent

A browser-playable Three.js port of Descent, bundling shareware Episode 1 and supporting the full game with your own copy.
Platforms:Web
Stars89
Updated1 month ago
LicenseMIT
Release2026
Genre: FPS
Theme: Sci-Fi
Halted
GLFrontier screenshot
GLFrontier

Clone of Elite II

GLFrontier reimplements the Atari ST game Frontier, built on reverse-engineered code plus parts from the Hatari emulator.
Platforms:WindowsLinux
Stars88
Updated10 years ago
LicenseUnknown
Release2013
Genre: Action
Theme: Sci-Fi
Sporadic
No preview
NakedAVP

Clone of Aliens Versus Predator

An SDL3 source port of Aliens Versus Predator Gold for Windows, macOS and Linux; needs the original game data.
Platforms:WindowsLinuxOSX
Stars84
Updated7 months ago
LicenseUnknown
Release2022
Genre: FPS
Theme: Sci-Fi
Sporadic
No One Lives Forever Modernizer screenshot
No One Lives Forever Modernizer

Clone of The Operative: No One Lives Forever

A Windows patch for No One Lives Forever that fixes bugs, restores multiplayer and adapts the game to modern resolutions.
Platforms:Windows
Stars83
Updated8 months ago
LicenseUnknown
Release2019
Genre: FPS
Theme: Comedy
Halted
Phoenix DOOM screenshot
Phoenix DOOM

Clone of Doom

A remaster of the 3DO version of DOOM for Windows, macOS and Linux, based on its official source release.
Platforms:WindowsLinuxOSX
Stars80
Updated6 years ago
LicenseMIT
Release2019
Genre: FPS
Theme: Sci-Fi
Archived
No preview
OpenSR

Clone of Space Rangers 2: Dominators

An archived, partially complete open-source engine for Space Rangers 2 that needs files from the "Reboot" release.
Platforms:WindowsLinuxOSX
Stars77
Updated9 years ago
LicenseGPL-3.0
Release2011
Genre: Adventure
Theme: Sci-Fi
Halted
No preview
Star Fighter

Clone of Star Fighter

The recovered 1995 3DO port source for Star Fighter, released in 2024, differing in several ways from the Acorn original.
Platforms:3DO
Stars77
Updated2 years ago
LicenseUnknown
Release2024
Genre: space simulator
Theme: Sci-Fi
Halted
No preview
Tread Marks

Clone of Tread Marks

Platforms:WindowsOSX
Stars77
Updated9 years ago
LicenseGPL3*
Release2017
Genre: Racing
Theme: Sci-Fi
Active
OpenDR screenshot
OpenDR

Clone of Dark Reign: The Future of War

A work-in-progress OpenRA mod recreating Auran's 1997 RTS Dark Reign, using content from the free demo.
Platforms:WindowsLinuxOSX
Stars75
Updated2 months ago
LicenseGPL-3.0
Release2018
Genre: Real-Time Strategy
Theme: Sci-Fi
Sporadic
Abuse 2025 screenshot
Abuse 2025

Clone of Abuse

A modern SDL2 port of Abuse (1996), adding high-resolution graphics, gamepad support, a level editor, and LAN co-op/deathmatch.
Platforms:WindowsLinuxOSX
Stars73
Updated6 months ago
LicenseUnknown
Release2024
Genre: Action
Theme: Horror
Halted
Full Metal Jacket screenshot
Full Metal Jacket

Clone of Full Metal Jacket

Preserves the complete executable, data, and source of Full Metal Jacket (1995), playable via DOSBox and rebuildable with Watcom C/C++.
Platforms:Windows
Stars73
Updated3 years ago
LicenseUnknown
Release2019
Genre: Action
Theme: Sci-Fi
Halted
No preview
SCSharp

Clone of StarCraft

SCSharp is a C# remake of the 1998 real-time strategy game StarCraft.
Platforms:Windows
Stars73
Updated5 years ago
LicenseUnknown
Release2010
Genre: Real-Time Strategy
Theme: Sci-Fi
Halted
Clonepoint screenshot
Clonepoint

Clone of Gunpoint

Clonepoint is a free, open-source clone of Gunpoint for Linux and Windows, with custom level support via the Tiled map editor.
Platforms:WindowsLinux
Stars71
Updated2 years ago
LicenseGPL-3.0
Release2015
Genre: Platform
Theme: Sci-Fi
Active
OpenE2140 (OpenRA) screenshot
OpenE2140 (OpenRA)

Clone of Earth 2140

A work-in-progress OpenRA-based remake of the 1997 RTS Earth 2140, now in multiplayer alpha.
Platforms:WindowsLinuxOSX
Stars71
Updated14 days ago
LicenseGPL-3.0
Release2022
Genre: Real-Time Strategy
Theme: Sci-Fi
Halted
No preview
Signus: The Artefact Wars

Clone of Signus: The Artefact Wars

The original developers' 2002 open-source release of their 1998 turn-based strategy war game, Signus: The Artefact Wars.
Platforms:WindowsLinux
Stars70
Updated2 years ago
LicenseGPL-2.0
Release2015
Genre: Turn-Based Strategy
Theme: Sci-Fi
Archived
Another World JS screenshot
Another World JS

Clone of Another World

An archived JavaScript/HTML5 reimplementation of Another World that interprets the original game's own bytecode, with a rewind feature.
Platforms:Web
Stars69
Updated4 years ago
LicenseUnknown
Release2020
Genre: Adventure
Theme: Sci-Fi
Halted
Machines: Wired For War screenshot
Machines: Wired For War

Clone of Machines: Wired for War

Official GL-ported source code release of Machines: Wired For War, a 3D RTS, published with permission from Night Dive Studios.
Platforms:WindowsLinux
Stars68
Updated4 years ago
LicenseGPL-3.0
Release2020
Genre: Real-Time Strategy
Theme: Sci-Fi
Halted
Good Robot screenshot
Good Robot

Clone of Good Robot

This is the official source code for Good Robot, a procedurally generated shoot-'em-up with light RPG elements by Pyrodactyl Games.
Platforms:WindowsLinuxOSX
Stars66
Updated6 years ago
LicenseMIT
Release2020
Genre: Shooter
Theme: Post-Apocalyptic
Archived
No preview
Homeworld

Clone of Homeworld

Platforms:Windows
Stars66
Updated11 years ago
LicenseUnknown
Release2015
Genre: Real-Time Strategy
Theme: Sci-Fi
Halted
Another World Suite screenshot
Another World Suite

Clone of Another World

Another World Suite is a Rust implementation of the Another World game engine, compiled to WebAssembly to run in a browser.
Platforms:Web
Stars65
Updated3 years ago
LicenseMIT
Release2020
Genre: Adventure
Theme: Sci-Fi
Archived
No preview
Heavy Metal: F.A.K.K. 2

Clone of Heavy Metal: F.A.K.K. 2

This is the official released source code for Heavy Metal: F.A.K.K. 2, not a third-party remake; the project is archived.
Platforms:Windows
Stars65
Updated6 years ago
LicenseUnknown
Release2020
Genre: Shooter
Theme: Cyberpunk
Halted
No preview
Total Annihilation 3D

Clone of Total Annihilation

A real-3D OpenGL reimplementation of Total Annihilation, requiring the original game's resource files.
Platforms:WindowsLinuxOSX
Stars64
Updated4 years ago
LicenseGPL-2.0
Release2017
Genre: Real-Time Strategy
Theme: Sci-Fi
Halted
libnpengine screenshot
libnpengine

Clone of Steins;Gate

libnpengine is a free reimplementation of the Nitroplus visual novel engine for Linux, currently able to run Steins;Gate and others.
Platforms:Linux
Stars64
Updated7 years ago
LicenseLGPL-3.0
Release2014
Genre: Adventure
Theme: Anime

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