Free & Open Source Simulation Games
256 free, open-source simulation games — real clones and remakes you can download, inspect the source of, and modify. Not just free to play: the code itself is open.
Active
Original game image
Original game imageClone of Dungeon Keeper 2
A Java/jMonkeyEngine remake of Dungeon Keeper II aiming for a faithful version 1.7 using the original game assets.
Sporadic
Clone of The Sims
A C# Windows frontend for The Sims, built on FreeSO, adding 3D visuals and a modern UI to the original 2D game.
Platforms:Windows
Stars492
Updated1 year ago
LicenseUnknown
Release2017
Genre: Simulation
Theme: Management
Active
Clone of Elite
The cassette version of Ian Bell and David Braben's 1984 Elite source code, reformatted and documented by Mark Moxon, not reconstructed.
Active
Clone of FreeSpace 2
FS2 Open, the FreeSpace 2 Source Code Project, is an open-source build of FreeSpace 2 targeting Windows, Linux, and macOS.
Platforms:WindowsLinuxOSX
Stars487
Updated1 month ago
LicenseUnknown
Release2013
Genre: Action
Theme: Sci-Fi
Active
Original game image
Original game imageClone of Ace Combat 6: Fires of Liberation
A work-in-progress Windows port of Ace Combat 6 made by statically recompiling its Xbox 360 code; US game copy required.
Stars484
Updated2 months ago
LicenseBSD-3-Clause
Release2026
Genre: Simulation
Theme: —
Active
Clone of Elite
The fully documented original Commodore 64 source code for Elite (1985), annotated line-by-line and built into four accurate variants.
Active
Clone of Lunar Lander
An open-source programming language whose example programs include recreations of classic games like Pac-Man and Tetris.
Active
Clone of The Sims 2
An early Unity-based re-implementation of The Sims 2, with a working main menu and basic neighborhood view.
Active
Active
Clone of BVE Trainsim
An open-source 3D cab-view train simulator that runs BVE, BVE5 and Mechanik routes and BVE trains.
Platforms:WindowsLinuxOSX
Stars377
Updated1 month ago
LicenseUnknown
Release2015
Genre: Simulation
Theme: —
Active
Clone of Elite
An open-source space trading and combat simulator with entirely original assets, inspired by the classic game Elite.
Active
Original game image
Original game imageClone of Microsoft Train Simulator
A free, open-source train simulator for Windows built to run the widest possible range of existing train and route content.
Halted
Clone of RimWorld
A Unity tutorial project and base-building game skeleton inspired by Dwarf Fortress and RimWorld.
Platforms:WindowsLinuxOSX
Stars325
Updated1 year ago
LicenseGPL-3.0
Release2017
Genre: Simulation
Theme: Sci-Fi
Active
Clone of The Sims
An open-source engine recreation of The Sims 1 with expanded gameplay, requiring the original game's files to run.
Platforms:WindowsLinux
Stars319
Updated2 months ago
LicenseUnknown
Release2015
Genre: Simulation
Theme: Management
Active
Original game image
Original game imageClone of Animal Crossing
A work-in-progress decompilation of the Nintendo 64 game Animal Forest, rebuilding an identical ROM rather than a port.
Halted
Original game image
Original game imageClone of Caesar III
An open-source remake of Caesar III on its own SDL2-based engine, playable but still in an early, experimental stage.
Platforms:WindowsLinuxOSX
Stars296
Updated9 years ago
LicenseUnknown
Release2014
Genre: Simulation
Theme: Management
Halted
Clone of Story of Seasons series
A farming-sim clone built in Godot with crops, town trading, and a day cycle, though some interior areas remain inaccessible.
Platforms:WindowsLinuxOSX
Stars293
Updated6 years ago
LicenseMIT
Release2019
Genre: Simulation
Theme: Anime
Halted
Active
Clone of Space Station 13
An open-source, pre-alpha 3D revival of Space Station 13, built in Unity and expanding *beep's original SS3D demo.
Sporadic
Original game image
Original game imageClone of SimCity
An ongoing, browser-playable SimCity clone built with Three.js under the MIT License, with no mobile support yet.
Active
Clone of RollerCoaster Tycoon
A C++17 recreation aiming to capture the look, feel, and gameplay of RollerCoaster Tycoon 1 and 2, semi-playable in-browser via WebAssembly.
Platforms:WebWindowsLinux
Stars255
Updated1 month ago
LicenseUnknown
Release2015
Genre: Simulation
Theme: Management
Halted
Original game image
Original game imageClone of RimWorld
An early-development fantasy colony sim adding RPG elements like classes and leveling to a RimWorld-style formula, built in C#/MonoGame.
Halted
Clone of RimWorld
A RimWorld mod distributed as a Harmony-patched DLL, with separate builds maintained for each RimWorld version.
Platforms:WindowsLinuxOSX
Stars249
Updated1 year ago
LicenseMIT
Release2016
Genre: Simulation
Theme: Sci-Fi
Active
Clone of Buzz Aldrin's Race Into Space
Race Into Space is the actively maintained free-software continuation of Buzz Aldrin's 1993 Race Into Space.
Platforms:WindowsLinuxOSX
Stars228
Updated1 month ago
LicenseGPL-2.0
Release2011
Genre: Strategy
Theme: Management
Active
Original game image
Original game imageClone of Harvest Moon 64
Harvest Moon 64 Decomp is a full decompilation of the North American and Japanese ROMs into matching, buildable source code.
Sporadic
Clone of SimCity
A SimCity-inspired city simulation for the Raspberry Pi RP2040, inspired by the Arduboy game MicroCity.
Active
Clone of Viva Piñata: Trouble in Paradise
An unofficial recompilation of Viva Pinata: Trouble in Paradise with native rendering and mod support.
Stars194
Updated1 month ago
LicenseUnknown
Release2026
Genre: Simulation
Theme: —
Halted
Clone of Elifoot 98
EliFUT is an open-source Android football-manager game inspired by Elifoot 98, using FIFA 15 data and free on Google Play.
Platforms:Android
Stars189
Updated6 years ago
LicenseApache-2.0
Release2015
Genre: Sports
Theme: Management
Halted
Original game image
Original game imageClone of Star Raiders
A fully documented, reverse-engineered assembly-language source of Atari's 1980 Star Raiders, rebuilt directly from the ROM binary.
Active
Halted
Clone of Ace Combat: Assault Horizon
An open-source reimplementation of Ace Combat: Assault Horizon's rendering and physics, without Dog Fight Mode.
Platforms:WindowsLinuxOSX
Stars175
Updated4 years ago
LicenseMIT
Release2014
Genre: Action
Theme: Modern Military
Sporadic
Clone of Creatures
An open-source engine for the Creatures artificial life games; it needs the original data files and is still in progress.
Platforms:WindowsLinuxOSX
Stars166
Updated5 months ago
LicenseLGPL-2.1
Release2020
Genre: Simulation
Theme: —
Halted
Clone of King under the Mountain
A Java game built with LibGDX, originally developed by Rocket Jump Technology and released open source under the MIT license.
Halted
Original game image
Original game imageClone of Days of Thunder
Recovered source code for an unpublished NES Days of Thunder, distinct from the 1990 Mindscape release, from Chris Oberth's archives.
Active
Clone of Theme Park World
An early, not-yet-playable re-implementation of Theme Park World that uses the original game's assets.
ActiveOriginal game image
Original game imageClone of Harvest Moon 64
A native PC port of Harvest Moon 64 made by static recompilation, with high framerates, widescreen and mod support.
Stars154
Updated1 month ago
LicenseGPL-3.0
Release2026
Genre: Simulation
Theme: —
Active
Original game image
Original game imageClone of Banjo-Kazooie: Nuts & Bolts
reNut, a recompilation of Banjo-Kazooie: Nuts & Bolts that needs the US version of the game.
Stars146
Updated1 month ago
LicenseUnknown
Release2026
Genre: Action
Theme: —
Halted
Clone of Elite
A Windows remake of Elite built with Allegro and DirectX, reaching Release 1.0 on 22 July 2001 after several betas.
Active
Clone of Outpost
A C++ redesign of Sierra's 1994 colony game Outpost, keeping its core concepts in a more responsive game.
Platforms:Windows
Stars143
Updated3 months ago
LicenseBSD-3-Clause
Release2018
Genre: Simulation
Theme: Sci-Fi