Free/Libre Open-source Games - Steam

Co-operative top-down shooter game available for free. An epic bug hunt featuring a unique blend of co-op play and squad-level tactics.

Amnesia: A Machine for Pigs

Game on Steam | Source Code | GNU General Public License v3.0 | Website

From the creators of Amnesia: The Dark Descent and Dear Esther comes a new first-person horror game that will drag you to the depths of greed, power and madness. It will bury its snout into your ribs and it will eat your heart.

Amnesia: The Dark Descent

Game on Steam | Source Code | GNU General Public License v3.0 | Website

Amnesia: The Dark Descent, a first person survival horror. A game about immersion, discovery and living through a nightmare. An experience that will chill you to the core.

Astral Shipwright

Game on Steam | Source Code | BSD 3-Clause "New" or "Revised" License | Website

Build and upgrade your personal ship to travel around a strange planet.

Barony

Barony is the premier first-person roguelike with cooperative play. Cryptic items, brutal traps, and devious monsters await you. Conquer the dungeon alone, or gather a party in co-op with iconic and unusual RPG classes. Get ready to try, and die, and try again with a new dungeon every time you play!

Battle for Wesnoth

The Battle for Wesnoth is an open source, turn-based strategy game with a high fantasy theme. Explore the four corners of Irdya in seventeen solo campaigns and dozens of multiplayer maps, taking part in countless adventures as you go.

Bitburner

Bitburner is a programming-based incremental game. Write scripts in JavaScript to automate gameplay, learn skills, play minigames, solve puzzles, and more in this cyberpunk text-based incremental RPG.

Blender

Software on Steam | Source Code | Website | Donate

Blender is the free and open source 3D creation suite. Free to use for everyone, for any purpose.

Break Arcade Games Out

Game on Steam | Source Code | License Public Domain | Website | Donate

What if Breakout was the only arcade game people could make? An open-source game, written entirely on a live stream.

Burning Knight

Game on Steam | Source Code | Donate

Steal everything you can and flee from the Burning Knight's castle in this action-packed roguelike! The game features tight bullet hell, tons of items, characters to meet... and secrets!

BYTEPATH

BYTEPATH is a replayable arcade shooter with a focus on build theorycrafting. Use a massive skill tree, many classes and ships to create your own builds and defeat an ever increasing amount of enemies.

Cataclysm: Dark Days Ahead

The epitome of a modern traditional roguelike: with turn-based play and a RPG-like skill progression system, it hearkens back to some of the major aspects of this genre. This game has an incredible depth, with a deep inventory system, vehicles and boats, NPCs with their own stories, and more.

Cendric

Game on Steam | Source Code | Tutorials & Help | Website

Cendric combines 2D RPG and Platformer elements in one indie game, featuring both a sidescroller and top-down view. The player explore a world by completing levels and quests, following the story of a boy with no memory and discovering the magical but dangerous world of Admantris.

Charge Kid

A challenging puzzle-platformer where each jump is a puzzle.

Cortex

The Psychedelic Tunnel-Runner.

Crystal Picnic

Game on Steam | Tutorials & Help | (incomplete) Source Code | Website

WARNING: THIS GAME ISN'T AVAILABLE ON STEAM ANYMORE, BUT YOU CAN STILL DOWNLOAD IT FROM THE WEBSITE.

Crystal Picnic is a lighthearted and colorful tribute to the classic era of action RPGs! Join a sarcastic gardener and a wannabe knight as they journey across the kingdom chasing after ants who stole magic crystals from the castle.

DDraceNetwork

Game on Steam | Tutorials & Help | Source Code | Website | Forums

DDraceNetwork is a cooperative racing mod of Teeworlds. What started as a simple mod is now a big cooperative platformer experience! Choose from hundreds of available maps, race your way to the finish line and help your friends. Collaborate and compete with players all over the world.

Death and Taxes

In this 2D, short narrative-based game, you assume the role of the Grim Reaper... on an office job. Your job is to decide which people are going to live or die. The consequences of your choices are yours to bear, while the mystery of your incarnation awaits revelation!

Defold

Software on Steam | Source Code | License Apache 2.0 | Website | Donate

Defold is a free and open game engine used for development of desktop, mobile and web games.

Destination Sol

Pilot your ship in the seamless open world made of space, planets, and more. Find new ships and equipment, find allies and beat all the enemies in this open source space shooter!

DwarfCorp

Build a colony of ruthless capitalist Dwarves in a strange fantasy land.

Endless Sky

Game on Steam | Tutorials & Help | Source code | Website | News

Endless Sky is a 2D space trading and combat game inspired by the classic Escape Velocity series. Work your way up from a relatively wimpy shuttle, cargo ship, or fighter, to a highly upgraded and customized flagship or to a massive fleet of warships or freighters.

Epicinium

Epicinium is a strategy game where nature is a finite resource. No need to wait for your move, thanks to fast, simultaneous turns. Your economy and troops are influenced by the environment and increasingly severe weather effects. Is it worth winning a war when you end up conquering dirt and ash?

Flotilla

Game on Steam | Source Code | zlib License | Website

Lead your orbital battleships to victory in Flotilla! Fight, trade, and explore new planets in your journey through the galaxy. Featuring tactically rich 3D combat, flank and surprise the enemy from any direction. And when the dust settles, generate another uniquely randomized universe for a brand-spanking new adventure!

FreedroidRPG

FreedroidRPG is an open source sci-fi role playing game, where the player (playing as Tux) fights against hordes of bots in order to free humanity from rebel bots whom know no mercy.

Godot Engine

Software on Steam | Source Code | License MIT | Website | Donate

Godot Engine is a feature-packed, cross-platform game engine to create 2D and 3D games from a unified interface. It provides a comprehensive set of common tools, so that you can focus on making games without having to reinvent the wheel.

Gravity Bone

Game on Steam | Source Code | GNU General Public License v2.0 | Website

To make it in Nuevos Aires, one needs nerves of silk and the filthiest of hands.

Half-Earth Socialism

Game on Steam | Source Code | GNU AFFERO GENERAL PUBLIC LICENSE | Website

Try your hand as a global planner of a future society. Play with a wide range of technologies and policies spanning different fields and ideologies. Will you lead the world to ecological utopia or planetary ruin?

Hedgewars

Turn-based strategy, artillery, action and comedy game, featuring the antics of pink hedgehogs with attitude as they battle from the depths of hell to the depths of space.

Helium Rain

Game on Steam | Source Code | BSD 3-Clause "New" or "Revised" License | Website | Tutorials & Help

Trade your wares and eliminate the competition in a cutthroat world. Buy new ships and stations to mine and haul resources. Explore the vast emptiness of space.

HookSharks

Hooksharks is a local multiplayer game about glory, and most of all, battling sharks with giant hooks attached to them.

HyperRogue

A tactical puzzle/roguelike on a hyperbolic plane.

Ingnomia

Following in the footsteps of Dwarf Fortress and Gnomoria, this game aims to provide the best experience of both worlds. The graphics and accessibility of Gnomoria and the depth and rich content of Dwarf Fortress.

KeeperRL

Game on Steam | Tutorials & Help | Source code | Website | News

Ambitious dungeon simulator with roguelike and RPG elements. Take the role of an evil wizard and study the methods of black magic. Equip your minions and explore the world, murder innocent villagers and burn their homes. Build your dungeon, lay traps and prepare for an assault of angry heroes.

Koi Farm

Koi Farm is a game about playing with koi ponds. Explore an infinite number of procedurally generated koi patterns by crossbreeding your fish, and discover new mutations as you go along.

Krita

Software on Steam | Source Code | GNU General Public License v3.0 | Website | Donate

Krita is a powerful, open source and community-driven digital art tool for illustrators, concept designers, animators, comic book artists, game developers, and anyone who wants to express themselves through the creation of visual art.

Lazy Chess

Lazy Chess is a new non-profit chess game that narrows your choices down to the best 2 possible moves per turn. The moves provided can always win the game, but how strong are your decisions? Fewer moves. More fun.

Little Big Adventure

Game on Steam | Source Code (classic) | Source Code (community) | Licence GPLv2 | Facebook

Originally released in 1994, Little Big Adventure, also known as Relentless: Twinsen’s Adventure, is an action-adventure RPG designed by Frédérick Raynal. The source code for both orginal games was released in 2021 under floss license, however the assets are not floss.

Little Big Adventure 2

Game on Steam | Source Code (classic) | Source Code (community) | Licence GPLv2 | Facebook

The sequel of Little Big Adventure. After saving the world from the evilish Doctor Funfrock, Twinsen is now ready to face a new threat coming from outer space. The source code is floss, but the assets are not floss.

Marvellous Inc.

Marvellous Inc. is a programming puzzle game, where you program robots to solve tasks.

McOsu

A free open-source circle-clicking rhythm game practice client for osu! beatmaps with Virtual Reality support. McOsu is developed separately from and has no direct affiliation with osu! or ppy Pty Ltd.

MegaGlest

MegaGlest is an open source cross-platform 3D real-time strategy (RTS) game, where you control the armies of one of seven different factions: Tech, Magic, Egypt, Indians, Norsemen, Persian or Romans. The game is setup in one of 17 naturally looking settings, which -like the unit models- are crafted with great appreciation for detail.

Mindustry

Game on Steam | Source code | Website | Tutorials & Help

An open-ended tower-defense game with a focus on resource management.

Monster RPG 2

Game on Steam | (incomplete) Source code | Website

WARNING: THIS GAME ISN'T AVAILABLE ON STEAM ANYMORE, BUT YOU CAN STILL DOWNLOAD IT FROM THE WEBSITE.

Monster RPG 2 is a fantasy quest that spans continents and worlds and lets you take a simple villager and develop her into a hero with the power to save her world.

Naev

Naev is a game about space exploration, trade and combat. Players travel the galaxy and earn money by trading, fighting and performing missions.

OBS Studio

Free and open-source software for video recording and live streaming

One Hour One Life

Game on Steam | Source code | Website | News | Forums

A multiplayer survival game of parenting and civilization building. Get born to another player as your mother. Live an entire life in one hour. Have babies of your own in the form of other players. Leave a legacy for the next generation as you help to rebuild civilization from scratch. Updated weekly.

One Manga Day

Manga are comics created in Japan. The problem for most people is, as they're made in Japan they're only produced in Japanese; someone has to translate them to English! Is one man able to accomplish this? Is there more to his team's relationships other than business? Can everything in a translator's life be simple and clear?

Open Hexagon

Game on Steam | Source Code | License AFL | Website

Open Hexagon is a FOSS clone of Super Hexagon, a minimal action game. A fast-paced adrenalinic arcade game that's easy to learn but hard to master!

OpenTTD

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

Penumbra Overture

Penumbra: Overture is a first person survival horror game, emphasizing on survival and problem solving instead of mindless violence and gore.

Pixelorama

Software on Steam | Source Code | License MIT | Website | Donate

Unleash your creativity with Pixelorama, a powerful and accessible open-source pixel art multitool. Whether you want to create sprites, tiles, animations, or just express yourself in the language of pixel art, this software will realize your pixel-perfect dreams with a vast toolbox of features.

PixiEditor - Pixel Art Editor

Software on Steam | Source Code | GNU Lesser General Public License v3.0 | Website | Donate

PixiEditor is a pixel art editing software. Create beautiful sprites for your games and edit images. All packed in an eye-friendly dark theme. Have you ever used Photoshop, Gimp or Aseprite? We want users to get familiar with the tool quickly and with ease.

Quadrilateral Cowboy

Game on Steam | Source Code | GNU General Public License v3.0 | Website

When you have a top-of-the-line hacking deck armed with a 56.6k modem and a staggering 256k RAM, it means just one thing: you answer only to the highest bidder.

Quaver

Quaver is a community-driven and open-source competitive rhythm game with two game modes and online leaderboards. Create your own maps or challenge the world in online multiplayer matches.

Red Eclipse 2

Game on Steam | Source Code | Website | Forums | Donate

Building on over 12 years of gameplay design, Red Eclipse 2 focuses on fast paced, agile, easily accessible first person shooter gameplay. For creators, the full power of the Tesseract engine is at your fingertips in the included realtime multiplayer editor.

Relic Hunters Zero

Game on Steam | Source Code | Website | Forums

Relic Hunters Zero is a game about shooting evil space ducks and evil space turtles with tiny cute guns. It’s fast, it’s tactical, and feels delicious and smooth to play. Unlock new weapons, characters and relics to defeat the Ducan Commander.

ROTA

Game on Steam | Source Code | GNU General Public License v3.0 | Website | Forums

In ROTA gravity bends beneath your feet! Move blocks and twist gravity to solve puzzles. Collect all 50 gems and explore 8 vibrant worlds!

Ryzom

Game on Steam | Source Code | Website | News | Forums

Enter a unique science fantasy MMORPG and dive into a unique organic living world !

Screeps

Game on Steam | Source Code | Website | News | Forums

Screeps is an open source MMO RTS sandbox game for programming enthusiasts, wherein the core mechanic is programming your units AI. You control your colony by writing JavaScript which operates 24/7 in the single persistent open world filled by other players on par with you.

Selfless Heroes

Solve puzzles by designing an AI for a team of selfless heroes. Test your algorithm, optimize it, and emerge victorious from the dungeon!

Session Seven

Session Seven is a free point & click adventure game in which you play as Ryan, an estranged father and husband who has just awoken, beaten, bruised, and alone in a locked cellar.

shapez.io

shapez.io is a game about building factories to automate the creation and processing of increasingly complex shapes across an infinitely expanding map.

ShareX

Software on Steam | Source Code | GNU General Public License v3.0 | Website | Donate

ShareX is a free and open source program that can capture or record selected area from the screen with a single keypress, automatically save them to your hard disk/clipboard, and instantly upload them to an image/file hosting service and then can copy the URL to your clipboard.

Shattered Pixel Dungeon

Game on Steam | Source Code | Website | News | Donate

Shattered Pixel Dungeon is a traditional roguelike dungeon crawler that's simple to start but hard to master!

Simutrans

Simutrans is a freeware and open-source transportation simulator. Your goal is to establish a successful transport company. Transport passengers, mail and goods by rail, road, ship, and even air. Interconnect districts, cities, public buildings, industries and tourist attractions

Snake

Play the classic that transcends generations.

SNKRX

SNKRX is an arcade shooter roguelite where you control a snake of heroes that automatically attack nearby enemies. Combine different heroes to unlock class bonuses and create unique builds, and steer your unstoppable party as they ravage through endless waves of enemies.

Solaris

Discover a space strategy game filled with conquest, betrayal and subterfuge. Build alliances, make enemies and fight your way to victory and galactic domination. Will you conquer the galaxy?

Soldat

Soldat is a unique 2D (side-view) multiplayer action game. It has been influenced by the best of games such as Liero, Worms, Quake, and Counter-Strike and provides a fast-paced gaming experience with tons of blood and flesh.

Space Station 14

Disasters, enemies, and incompetence conspire to make each shift aboard the station a unique and hellish experience. Sign up today to explore intricate game mechanics and enjoy limitless player interaction! (Nanotrasen Inc. is not responsible for injury, death, or worse).

Star Ruler 2

Game on Steam | Source Code | License MIT | Website

Massive scale 4X-RTS set in space. Control hundreds of planets, manipulate galactic politics, research numerous advanced technologies, and command thousands of units and hundreds of planets in your quest for galactic dominance.

SuperTux

Classic 2D jump'n'run sidescroller featuring Tux the penguin. Run and jump through multiple worlds, fighting off enemies by jumping on them, bumping them from below or tossing objects at them, grabbing power-ups and other stuff on the way.

Tales of Maj'Eyal

Tales of Maj’Eyal is a roguelike RPG, featuring tactical turn-based combat and advanced character building. Play as one of many unique races and classes in the lore-filled world of Eyal, exploring random dungeons, facing challenging battles, and developing characters with your own tailored mix of...

Teeworlds

Teeworlds is a free online multiplayer game, available for all major operating systems. Battle with up to 16 players in a variety of game modes, including Team Deathmatch and Capture The Flag. You can even design your own maps!

Termite

Game on Steam | Source Code | License GPLv3 | Donate

Termite is a psychedelic real-time action strategy experience. You are the leader of a termite hive with three objectives: collect food, produce ants and destroy alien colonies.

The Castle Doctrine

The Castle Doctrine is a massively-multiplayer game of burglary and home defense. It's 1991, and things are bad. You're a guy with a house and family. Other players are coming to take what's yours. Build security to stop them. Study their houses, buy tools, and break in to take what's theirs.

The Castles of Dr. Creep

Game on Steam | Source Code | Tutorials & Help | Website | Forums

Explore thirteen different castles, overcoming a variety of puzzles and traps while you attempt to escape.

The Colorful Creature

Game on Steam | Source Code | Donate

The Colorful Creature is difficult platformer with puzzle color mechanics. Play over 300 levels with diverse gameplay that have many items and hazards, in-game level editor, local multiplayer, endless run, customizable skins & hats, steam workshop and more!

The Powder Toy

The Powder Toy is a classic physics sandbox game, which simulates air pressure and velocity, heat, gravity and a countless number of interactions between different substances

The Secret of Tremendous Corporation

Explore the deepest SECRETs™ of the Tremendous Corporation®. Find out what happened to indie devs and save the gaming industry!

Thirty Flights of Loving

Game on Steam | Source Code | GNU General Public License v2.0 | Website

Explore the world of Thirty Flights of Loving through a first-person short story. Take a deep dive with high-flying schemers, lovelorn criminals, and more stray kittens than you can shake a stick at.

Thrive

An evolution simulation game. Take control of your species in the environment and edit your species as a whole. Compete with other evolving species for resources on an alien planet.

tModLoader

Mod on Steam | Source Code | Website | Donate

Dig, Fight, and Build your way through the world of player-created mods on Terraria with tModLoader - this DLC makes modding Terraria a reality!\ Note: In order to use this mod, you need to own Terraria on the Steam. Terraria is not FLOSS, but proprietary software.

Tomantenquark

Tomatenquark is a multiplayer & singleplayer first person shooter, a community homage to Cube 2: Sauerbraten.

Trigger Time

Trigger Time is a story-driven, top-down Shoot 'em up with a fun gravity gun and physics puzzles to solve. Blast your way through 9 levels filled with enemies, hazards and bizarre bosses. Along the way you'll take control of vehicles, pick up weapons, items and boosters.

Uebergame

A truly free and open source multiplayer shooter, no strings attached. Have casual deathmatch matches on various scenarios. Build your own levels with the ingame editor and assets that come with the game, or just play around and use it as a sandbox.

Vulture for NetHack

Vulture for NetHack is an isometric graphical interface for the roguelike engine: NetHack, the most celebrated member of the ancient and honorable family of games descended from Rogue and hence known as “roguelike”: bare-bones ASCII-graphics adventures set in randomly generated dungeons, in which the player fights monsters and collects items until he or she dies.

Warfork