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.

Halted
Alien3-C64 screenshot
Alien3-C64

Clone of Alien 3

This repository preserves Michael J Archer's complete 6502 assembly source code for the Commodore 64 version of Alien 3.
Platforms:C64
Stars63
Updated7 years ago
LicenseUnknown
Release2019
Genre: Action
Theme: Horror
Halted
No preview
Dune 2 - The Maker - Java version

Clone of Dune 2

This is a Java implementation of a real-time strategy game, built with the slick2d-maven framework, requiring Maven and Java 1.8.
Platforms:None
Stars63
Updated5 years ago
LicenseMIT
Release2012
Genre: Real-Time Strategy
Theme: Sci-Fi
Active
No preview
Q2REPRO

Clone of Quake 2

Q2REPRO is a Q2PRO fork built as a drop-in replacement for the official Quake II re-release engine.
Platforms:WindowsLinux
Stars63
Updated29 days ago
LicenseGPL-2.0
Release2023
Genre: FPS
Theme: Sci-Fi
Archived
No preview
Blood II: The Chosen

Clone of Blood II: The Chosen

This repository contains the officially released LithTech-engine source code for Blood II: The Chosen, released by Monolith.
Platforms:Windows
Stars62
Updated12 years ago
LicenseUnknown
Release2014
Genre: FPS
Theme: Sci-Fi
Halted
No preview
SiN Gold Game Source

Clone of SiN

Night Dive Studios' official source release of SiN Gold, the 1998 Ritual Entertainment shooter built on a modified Quake II engine.
Platforms:Windows
Stars62
Updated6 years ago
LicenseUnknown
Release2020
Genre: FPS
Theme: Sci-Fi
Archived
No preview
Star Raiders for Atari 800

Clone of Star Raiders

A hand-typed transcription of the original Atari 800 Star Raiders source code, made from scanned printed listings.
Platforms:Atari
Stars61
Updated10 years ago
LicenseUnknown
Release2015
Genre: Action
Theme: Sci-Fi
Active
Elite-A screenshot
Elite-A

Clone of Elite

Elite-A is a fan-made enhancement of BBC Micro Elite, built by disassembling and extending the original game's object code.
Platforms:BBC Micro
Stars59
Updated11 days ago
LicenseUnknown
Release2021
Genre: Action
Theme: Sci-Fi
Halted
Iron Doom screenshot
Iron Doom

Clone of Doom

Iron Doom is a Doom source port written in Rust on the Chocolate Doom codebase, using Bevy's ECS to fix engine bugs.
Platforms:WindowsLinuxOSX
Stars59
Updated1 year ago
LicenseGPL-3.0
Release2024
Genre: FPS
Theme: Sci-Fi
Sporadic
No preview
vitaRTCW

Clone of Return to Castle Wolfenstein

A PS Vita port of id Software's open-source Return to Castle Wolfenstein single-player release.
Platforms:PSVita
Stars59
Updated4 months ago
LicenseGPL-3.0
Release2018
Genre: FPS
Theme: Sci-Fi
Active
No preview
Alien Breed 3D II The Killing Grounds

Clone of Alien Breed 3D II: The Killing Grounds

An actively maintained rebuild of the Alien Breed 3D II: The Killing Grounds engine, compatible with original game data or mods.
Platforms:Amiga
Stars57
Updated13 days ago
LicenseUnknown
Release2022
Genre: FPS
Theme: Horror
Active
Cryogenic screenshot
Cryogenic

Clone of Dune

A C# reimplementation of Dune's 1992 CD version that replaces original DOS assembly routines using the Spice86 x86 emulator.
Platforms:Windows
Stars57
Updated1 month ago
LicenseApache-2.0
Release2022
Genre: Adventure
Theme: Sci-Fi
Sporadic
Lilium Voyager screenshot
Lilium Voyager

Clone of Star Trek: Voyager – Elite Force

An open-source engine reimplementation of Star Trek: Voyager - Elite Force's Holomatch mode, built on the ioquake3-derived ioEF engine.
Platforms:WindowsLinuxOSX
Stars57
Updated4 months ago
LicenseGPL-2.0
Release2017
Genre: FPS
Theme: Sci-Fi
Halted
No preview
Pararena 2.0

Clone of Pararena

Source code of Pararena, John Calhoun's commercial Macintosh game published by Casady & Greene.
Platforms:Classic Mac OS
Stars56
Updated5 years ago
LicenseMIT
Release2016
Genre: Sports
Theme: Sci-Fi
Halted
No preview
Stardust rebuilt

Clone of Star Dust

A reverse-engineered ZX Spectrum source reconstruction of the 1987 game Stardust, made by its original developers.
Platforms:ZX Spectrum
Stars55
Updated8 years ago
LicenseUnknown
Release2017
Genre: Shmup
Theme: Sci-Fi
Halted
No preview
mechcommander2

Clone of MechCommander 2

A patched version of MechCommander 2's Microsoft-released source code, though the README doesn't detail what the patches change.
Platforms:Windows
Stars54
Updated3 years ago
LicenseBSD-2-Clause
Release2014
Genre: Real-Time Tactics
Theme: Sci-Fi
Active
BBC Micro disc Elite screenshot
BBC Micro disc Elite

Clone of Elite

Source code for the disc version of Elite on the BBC Micro, reconstructed from a disassembly and documented line-by-line by Mark Moxon.
Platforms:BBC Micro
Stars52
Updated11 days ago
LicenseUnknown
Release2021
Genre: Action
Theme: Sci-Fi
Halted
Javascript Delta screenshot
Javascript Delta

Clone of Delta

A self-described 'weekend homage' to the C64 shoot-em-up Delta, built in JavaScript and CSS, deliberately left unfinished.
Platforms:Web
Stars51
Updated1 year ago
LicenseMIT
Release2014
Genre: Shmup
Theme: Sci-Fi
Halted
No preview
Mega Man 3 (NES) Disassembly

Clone of Mega Man 3

A complete disassembly of the NTSC-U Mega Man 3 NES ROM, covering all code and data, reassembling byte-for-byte via the xkas-plus build.
Platforms:NES
Stars51
Updated5 years ago
LicenseUnknown
Release2017
Genre: Platform
Theme: Sci-Fi
Halted
ZGloom screenshot
ZGloom

Clone of Gloom

A from-scratch re-implementation of the Amiga FPS Gloom, including support for its Zombie Massacre expansion.
Platforms:WindowsLinux
Stars49
Updated3 years ago
LicenseUnknown
Release2019
Genre: FPS
Theme: Sci-Fi
Halted
No preview
Hardwar

Clone of Hardwar

This is a pre-alpha remake of the sci-fi flight-sim game Hardwar, with no playable build yet, built via Bower and CMake.
Platforms:WindowsLinuxOSX
Stars45
Updated10 years ago
LicenseGPL-3.0
Release2011
Genre: Action
Theme: Sci-Fi
Halted
RAD screenshot
RAD

Clone of Radix: Beyond the Void

RAD is a from-scratch engine recreation of the 1995 DOS shooter Radix: Beyond the Void with OpenGL rendering.
Platforms:Windows
Stars44
Updated1 year ago
LicenseGPL-2.0
Release2020
Genre: FPS
Theme: Sci-Fi
Halted
FreedroidRPG screenshot
FreedroidRPG

Clone of Paradroid

FreedroidRPG is an isometric 3D RPG set on future Earth, blending real-time action with dialogue-driven role-playing over 12 hours.
Platforms:WindowsLinux
Stars43
Updated1 year ago
Licensebitstream-vera
Release2015
Genre: Shmup
Theme: Fantasy
Active
Apple II Elite screenshot
Apple II Elite

Clone of Elite

This is the annotated original 6502 assembly source for the Apple II version of Elite, assembling into five byte-accurate variants.
Platforms:Apple II
Stars42
Updated11 days ago
LicenseUnknown
Release2024
Genre: Action
Theme: Sci-Fi
Active
FreedroidClassic screenshot
FreedroidClassic

Clone of Paradroid

FreedroidClassic is a GPL-licensed remake of Paradroid, with some improvements and extensions, for Windows and Linux.
Platforms:WindowsLinux
Stars42
Updated1 month ago
LicenseGPL-2.0
Release2012
Genre: Shmup
Theme: Fantasy
Halted
No preview
Space Ace IIgs

Clone of Space Ace

A reverse-engineered rebuild of the 1990 Apple IIgs port of Space Ace, rewritten to run from a hard disk instead of floppy disks.
Platforms:Apple II
Stars42
Updated11 years ago
LicenseUnknown
Release2015
Genre: Action
Theme: Sci-Fi
Archived
No preview
galaga-7800

Clone of Galaga

Platforms:Atari
Stars42
Updated11 years ago
LicenseUnknown
Release2015
Genre: Action
Theme: Sci-Fi
Active
6502 Second Processor Elite screenshot
6502 Second Processor Elite

Clone of Elite

The original 1985 BBC Micro assembly source for Elite, documented by Mark Moxon and buildable into byte-accurate historical discs.
Platforms:BBC Micro
Stars40
Updated11 days ago
LicenseUnknown
Release2020
Genre: Action
Theme: Sci-Fi
Active
Alien Arena screenshot
Alien Arena

Clone of Quake 3

A free arena FPS with a macabre sci-fi theme and 23 levels; its engine is GPL-licensed and actively developed for Linux and Windows.
Platforms:WindowsLinux
Stars40
Updated15 days ago
LicenseUnknown
Release2023
Genre: FPS
Theme: Sci-Fi
Halted
Atomic-Robokid screenshot
Atomic-Robokid

Clone of Atomic Robo-Kid

The original Commodore 64 conversion source for Atomic Robo-Kid, released by its own developer from his personal backups.
Platforms:C64
Stars40
Updated7 years ago
LicenseUnknown
Release2019
Genre: Shooter
Theme: Sci-Fi
Halted
No preview
F-Zero X

Clone of F-Zero X

A work-in-progress F-Zero X (N64) decompilation that rebuilds a byte-identical ROM but isn't yet organized for gameplay modding.
Platforms:N64
Stars40
Updated3 years ago
LicenseUnknown
Release2022
Genre: Racing
Theme: Sci-Fi
Active
JLud2D screenshot
JLud2D

Clone of Phantasy Star

JLud2D, a 2D engine once a Java desktop app, is being ported to TypeScript and Phaser 3 for browser demos like a Phantasy Star RPG remake.
Platforms:None
Stars40
Updated1 month ago
LicenseGPL-3.0
Release2018
Genre: RPG
Theme: Sci-Fi
Halted
No preview
Aliens vs. Predator Gold

Clone of Aliens Versus Predator

The released Windows source for Aliens versus Predator Gold, mirrored from a 2008 GameFront download; development here has halted.
Platforms:Windows
Stars39
Updated14 years ago
LicenseUnknown
Release2012
Genre: FPS
Theme: Sci-Fi
Halted
LinWarrior screenshot
LinWarrior

Clone of MechWarrior

Platforms:WindowsLinux
Stars38
Updated3 years ago
LicenseApache-2.0
Release2012
Genre: Simulation
Theme: Sci-Fi
Halted
xGreed screenshot
xGreed

Clone of In Pursuit of Greed

A Windows source port of the 1995 DOS shooter In Pursuit of Greed, adding mouse-look and higher resolution.
Platforms:Windows
Stars37
Updated4 years ago
LicenseUnknown
Release2020
Genre: FPS
Theme: Sci-Fi
Halted
Core Breach screenshot
Core Breach

Clone of Wipeout

CoreBreach is an anti-gravity combat racer built on the open-source Core3D engine, targeting Linux, Windows, macOS and Android.
Platforms:WindowsLinuxOSX
Stars36
Updated4 years ago
LicenseUnknown
Release2012
Genre: Racing
Theme: Sci-Fi
Halted
OpenXeen screenshot
OpenXeen

Clone of Might and Magic IV: Clouds of Xeen

An unfinished Java rewrite of the Might and Magic: World of Xeen engine with planned gameplay changes.
Platforms:None
Stars36
Updated8 years ago
LicenseUnknown
Release2016
Genre: RPG
Theme: Sci-Fi
Archived
JJFFE screenshot
JJFFE

Clone of Elite III

Platforms:WindowsOSX
Stars35
Updated11 years ago
LicenseUnknown
Release2015
Genre: Action
Theme: Sci-Fi
Halted
No preview
Mega Man 5 (NES) Disassembly

Clone of Mega Man 5

A complete disassembly of the NTSC-U Mega Man 5 (NES) ROM that reassembles byte-for-byte via the bundled xkas-plus build.
Platforms:NES
Stars34
Updated2 years ago
LicenseUnknown
Release2017
Genre: Platform
Theme: Sci-Fi
Active
Acorn Electron Elite screenshot
Acorn Electron Elite

Clone of Elite

A fully documented, hand-reconstructed disassembly of Elite for the Acorn Electron, buildable into disc or tape images.
Platforms:Acorn 32-bit
Stars33
Updated15 days ago
LicenseUnknown
Release2021
Genre: Action
Theme: Sci-Fi

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