Adventure games

• Egoboo - Action-adventure rogue-lite game

• Myst Online: Uru Live - MMO adventure game in where players interact with others to solve puzzles and advance the story.

Action role-playing games

• Ardentryst - Action/RPG sidescoller.

• Epic Inventor - Side-scrolling, Action RPG inspired by Terraria.

• FreedroidRPG - Diablo-style ARPG.

• Summoning Wars - Action roleplaying game for singleplayer or up to 8 players in multiplayer.

Art games

• Hummingbird - Infinite procedural musical exploration game.

• Passage - A simple experimental side scroller game intended as an abstract metaphor for the human condition.

Artillery games

• Apple Flinger - Angry Birds-clone for Android.

• Atomic Tanks - Multi-platform Scorched Earth clone similar to the Worms series.

• Cat-O-Pult - Castles/Worms type of a game, but in this one you use cats as your weapon of choice.

• Gusanos - Clone of the DOS game Liero.

• Warmux and OpenLierox - Clones of Worms.

Board games

• c4 - Connect Four game, with AI. Source code

• Desperate Gods - Online board game where no rules are enforced by the computer, and all moves are performed in a shared physical space. The game itself is a dark fantasy dungeon crawl for up to four players.

• Domination - Game based on the board game "Risk".

• Lichess (source code), Lucas Chess, 3D Hartwing Chess Set (source code) and DroidFish Android Chess App - Chess games.

• OGS Mahjong, Green Mahjong (source code) - Games of Mahjong.

• Quatter- Game of Quarto.

• Scrabble3D - Highly customizable Scrabble game. Supports Classic Scrabble, Superscrabble and also 3D games and own boards.

Card games

• PokerTH - Poker game.

• PySolFC, Solitaire.gg, Aisleriot - Collection of solitaire games.

Collectible card games

• Magarena - Single-player fantasy card game.

Construction and management simulation games

• Freeserf - Clone of The Settlers 1/Serf City.

• FreeTrain - Rail and business simulation inspired by the A-Train series of games.

• KeeperRL - Dungeon management and roguelike.

• LinCity-NG, Micropolis Web and 3d.city - Clones of SimCity.

• OpenSkyscraper - Clone of the simulation game SimTower.

• The Founder - Dystopian business-simulator. Source code

Fighting games

• OpenOMF - Remake of One Must Fall 2097.

Flight games

• FlightGear - Flight simulator.

• Triplane Classic - Sidescrolling dogfighting flying game

First-person-shooter

• AssaultCube Reloaded

• Digital Paint: Paintball 2 and Digital Paint: Paintball 3 - Fast-paced first-person shooter.

• FreeCS - Reimplementation of Counter-Strike 1.5.

• Nexuiz - Multiplayer first-person shooter.

• Quetoo - Multiplayer first person shooter based on id Tech2.

• Tremulous - Asymmetric team-based first-person shooter with real-time strategy elements. Source code

• Übergame - Realism like, multi-purpose, multiplayer, casual, first-person-shooter game.

• Unvanquished - First-person strategy shooter, pitting technologically advanced human soldiers against hordes of highly adaptable aliens.

Infinite runner games

• Biketris - Hybrid of block-stacking puzzle and endless runner.

• Red Runner

Metroidvania games

• Birdsong - Game about a bird that is about to leave the nest.

• Meteorite - Lowres FPS, inspired by Metroid Prime.

• The Diasporic Crypt - Libre game inspired by Castlevania, where you play a vampire who moves around in a portable teleporting catacombs underground.

MMORPGs

• BrowserQuest

• Daimonin

• Evol Online - 2D MMORPG. Source code

• ImperiumAO - Source code

• PlaneShift - 3D fantasy MMORPG.

• Stendhal - 2D MMORPG.

• The Mana World - 2D MMORPG. Source code

Music games

• Auto Rhythm - Rhythm game with auto generated note maps.

• Frets on Fire X - Highly customizable rhythm game supporting many modes of guitar, bass, drum, and vocal gameplay for up to four players.

• osu! (Source code) and McOsu - Based on the gameplay of a variety of popular commercial rhythm games.

• Performous - Karaoke, band games and dancing in the same package.

• StepMania - Advanced cross-platform rhythm game.

• Turnt Ninja - Fast-paced rhythm game that uses your own music.

• UltraStar Deluxe - Clone of SingStar.

Paddle-and-ball video games

• Deflector - Retro style, ball bouncing, arcade game.

Physics based games

• CaveExpress - 2D platformer with physics-based gameplay.

• Golems - 3D physics simulator.

• Gravity Box - Puzzle platformer where you have to use bullet's blast to push towards the finish points.

• Neverball - Puzzle game inspired by Super Monkey Ball.

• Nikki and the Robots - Physics platformer.

• OpenGOO - Clone of the physics based puzzle / construction game "World of Goo".

• Rigs of Rods - Vehicle simulator based on soft-body physics.

• Safety Blanket - Creepy blanket simulator.

• The Powder Toy - Physics sandbox game, which simulates air pressure and velocity, heat, gravity and a countless number of interactions between different substances.

• XMoto - 2D motocross platform game.

Platform games

• ativayeban and FallingTime - Clones of Fall Down.

• Bard's Lesson - Platform game in which you help a bard fox in his journey to become a maestro by mastering music notation.

• Fox Dash - Side scrolling 2D platformer for Android. Source code

• GOAT - An arcade game about a drunken space goat!

• JVGS - Minimalistic platform game.

• Mega Mario, SuperTux, ReTux and The Secret Chronicles of Dr. M. - Clones of Mario.

• Parallel Universe - Minimalist Yin and Yang Platformer.

• RickyD and xrick - Clones of Rick Dangerous.

• Tobu Tobu Girl - Arcade platformer where you have to save your cat who is floating into the atmosphere.

• Sienna - Simple one-button platformer.

• Sonic Robo Blast 2 - 3D fangame based on the Sonic the Hedgehog series with many mods.

• Spelunky Classic HD - Cave exploration / treasure-hunting game inspired by classic platform games and roguelikes

• Super Mario War - A Super Mario multiplayer game in where the goal is to stomp as many other Marios as possible. (Switch port)

• Super Methane Brothers, The Bub's Brothers - Clones of Bubble Bobble.

• The Legend of Edgar - Action platformer game.

Programming games

• Robocode - Programming game, where the goal is to develop a robot battle tank to battle against other tanks in Java or .NET.

Puzzle games

• 1010! Klooni - Minimalistic puzzle game.

• Bombman - Atomic Bomberman clone.

• Atomiks - Atomix clone.

• Crack Attack!, FreeBlocks and Panel Attack - Clones of the puzzle game Tetris Attack.

• Cuyo - Tetris-style puzzle game for up to two players.

• Gweled and Freegemas - Clones of Bejeweled.

• Hextris - Puzzle game inspired by Tetris.

• Lix and Rabbit Escape - Clones of Lemmings.

• Mice Men: Remix - Remake of the DOS game Mice Men.

• Mirror Magic - Arcade style puzzle game.

• OpenBlok - Clone of Tetris.

• Orbium - Clone of Log!cal.

• pocico - Puzzle game where the goal is to match the outer color with the inner color in every shape.

• Rocks'n'diamonds - Clone of Boulder Dash.

• Sudoku JS, Open Sudoku and Nudoku - Games of Sudoku

• Tanglet - Single player word-finding game based on Boggle.

• The Butterfly Effect - Clone of Crazy Machines.

• The lost Penguin - Guide laser beams through multiple mirrors to resolve the puzzles.

• Wizznic! - A difficult puzzle game with built-in puzzle-editor.

Puzzle-platformer games

• GlPortal - Clone of Portal.

• Minilens

• Nova the Squirrel - NES game with ability copying and puzzles.

Racing games

• Extreme Tux Racer and Tux Rider - Android Edition- High speed arctic racing games based on Tux Racer.

• Marble Marcher - Ray-traced racing game on the surface of evolving fractals.

• Speed Dreams - Motorsport simulation and racing game.

• Stunt Rally - Racing game with rally style of driving.

• The Open Racing Car Simulator - Car racing simulation.

• Trigger Rally - Fast-paced single-player racing game.

• VDrift - Racing simulator.

• Yorg - 3d racing game in the style of MicroMachines.

Real-time strategy games

• Battle City - Real-time action and strategy multiplayer game. You control a tank and your mission is to destroy enemy cities while defending your own.

• Bos Wars - Sci-fi RTS game.

• Gigalomania - RTS MegaLoMania-like god game.

• Globulation 2 - RTS featuring auto-tasking to units.

• Liberation Circuit - Rogue A.I. Simulator.

• Spring: 1944 - RTS game set in the final year of WWII.

Real-time tactics games

• MAXR - Remake of the real-time/turn-based strategy game M.A.X.

• Mr.Boom, SDL Bomber and Bombermaaan - Bomberman clones.

Roguelike games

• Fame - Fantasy roguelike game with graphics tiles, inspired mainly by ADOM.

• The Endless Dungeons - 8-bit style random dungeon game

Role-playing video games

• Andor's Trail - Single-player quest-driven fantasy RPG.

• Crossfire - Cooperative multiplayer graphical RPG and adventure game.

• Erebus - Classic point-n-click style RPG.

• GearHead - Mecha roguelike.

• Red Rogue - Sidescrolling platformer-roguelite with optional realtime movement.

• Tuxemon - Clone of Pokémon.

Sandbox games

• Gnomescroll, ClassiCube and Freeminer - Minecraft-clones.

• OpenSpades - Clone of the team-based first-person shooter and voxel-based sandbox Ace of Spades.

Sealth games

• Art Treachery - Stealthy art heist game.

Shoot 'em up games

• Bloodworks - Top-down survival action game where you fight against an endless waves of monsters.

• C-Dogs SDL - Clone of the shoot 'em up C-Dogs.

• Chromium B.S.U. - Fast paced, arcade-style, top-scrolling space shooter.

• Dave Gnukem - Retro-style 2D scrolling platform shooter, inspired by and similar to Duke Nukem 1.

• Friking Shark - Remake of the shoot 'em up game Flying Shark.

• Gang Garrison 2 - Multiplayer 'demake' of Team Fortress 2.

• Galaxy Forces V2 - 2D multiplayer space shooter, inspired by the Amiga classic Gravity Force.

• heXon - Twin-stick-shooter for up to four players

• Lisparuga - 2D shoot-em-up game inspired by Ikaruga. (GNU/Linux systems only)

• M.A.R.S. - 2D space shooter.

• Maelstrom - Clone of Asteroids

• NightHawk - Clone of Paradroid.

• Relic Hunters Zero - Online cooperative shooter/RPG. Source code

• Torrega Race - Simple space game inspired by Omega Race.

• Violetland - Cross-platform game similar to Crimsonland.

• Watch out for Snakes - Short low poly top down retro arcade shooter.

• Witch Blast - Roguelite dungeon crawl shooter heavily inspired from Binding Of Isaac.

Social simulation games

• Cart Life - Simulation game in which the player controls one of three street vendors, and attempts to run their shop whilst looking after their health, interests, and families. Source code

• Coming Out Simulator 2014 - Interactive game intended to help LGBT youth to understand their sexuality.

• Our Personal Space - Marriage survival sim set on a space colony in the near future.

• Two Interviewees - Short visual novel about the gender gap.

Space combat games

• Antares - Tactical space-combat game, combining elements of both arcade shooters and real-time strategy games.

• Bridge Command - An interactive ship simulator.

• EmptyEpsilon - A spaceship bridge simulator game

• The Pandoran War - 2D mission-based space shooter.

Sport games

• Bygfoot - Football/soccer management game.

• FooBillard - OpenGL-based billiards simulation game.

• Goal Rush - Fast paced arcade game where two-robots team will face each other to score the maximum of goals during short matchs.

• YSoccer - Retro style, multi-platform soccer game.

Third-person shooter games

• Army Men III

Tower defense games

• Anuto - Tower defense game for Android.

• Castle-Combat - Clone of the arcade game Rampart.

• The Last Stand

Turn based strategy games

• Ancient Beast - A turn based strategy game similar to Heroes of Might and Magic.

• Dominus - Multiplayer social strategy game. Source code

• Free Mars - Turn based strategy game about colonizing Mars.

• Necro - A text based Virus simulator similar to Plague Inc. Source code

• TripleA - Game based on Axis & Allies board game.

• webDiplomacy - Online version of the game Diplomacy. Source code

Turn-based tactics games

• Advanced Strategic Command and Crimson Fields - Clones of the turn based strategy game Battle Isle.

• OpenXcom and Xenowar - Clones of the X-Com series.

Vehicular combat games

• Armagetron Advanced - Multiplayer 3D clone of Tron.

• BZFlag - 3D online multi-player tank battle game.

• OpenC1 - Remake of Carmageddon

Walking simulator games

• november - Short horror/escape room/walking simulator.

• Slave Of God - Trippy psychedelic ride simulator.

• Wave Function Collapse - Infinite, procedurally generated city, assembled out of blocks.

• you used to be someone - Based on the developer experience having a major depressive episode.

Uncategorized

• 90 Second Portraits - Painting game

• Agar.io Clone - Simple Agar.io clone.

• Thrive - Game about the evolution of life.