http://crazycarscpc.free.fr/
http://www.plasmapong.com/plasma-pong/plasma-pong/
http://www.rpgtoolkit.net/
http://www.rtsoft.com/novashell/
http://www.sandboxgamemaker.com/
http://www.scirra.com/construct-classic
http://www.silversecond.com/WolfRPGEditor/
http://www.spheredev.org/
http://www.surfline.ne.jp/hachi/xsoldier.html
http://www.usgo.org/go-software
http://www.vbgore.com/Main_Page
http://www.zeldaroth.fr/us/zroth.php
http://www.zsnes.com/ (emulator/platform)
https://001gamecreator.com/
https://agateau.com/games/
https://app.assembla.com/spaces/openrpg/wiki
https://app.assembla.com/spaces/Project_Valkyrie2/wiki
https://archive.codeplex.com/?p=turnota
https://archive.codeplex.com/?p=voxeliq
https://blenderartists.org/t/devils-pinball/552785
https://carrot.soulweaver.fi/#links
https://cocainediesel.fun/
https://code.launchpad.net/~flosoft/s25rttr/trunk
https://conquertheworldbycode.wordpress.com/nostalgia-2/
https://dosgames.com/forum/about19706.html
https://dragengine.rptd.ch/
https://eblong.com/zarf/twilight/index.html
https://emulation.gametechwiki.com/index.php/Main_Page
https://en.wikipedia.org/w/index.php?title=GNU_Backgammon&action=edit&redlink=1
https://en.wikipedia.org/w/index.php?title=Golden_Age_of_Civilizations&action=edit&redlink=1
https://en.wikipedia.org/w/index.php?title=Kdegames&action=edit&redlink=1
https://en.wikipedia.org/w/index.php?title=Simon_Tatham%27s_Portable_Puzzle_Collection&action=edit&redlink=1
https://en.wikipedia.org/w/index.php?title=Simple_Solitaire_Collection&action=edit&redlink=1
https://en.wikipedia.org/w/index.php?title=Trigger_Rally&action=edit&redlink=1
https://en.wikipedia.org/wiki/M.U.G.E.N
https://enigma-dev.org/about.htm
https://futurepinball.com/
https://gdevelop-app.com/
https://github.blog/2014-01-06-github-game-off-ii-winners/
https://github.blog/2021-05-19-ludum-dare-48-staff-picks/
https://github.com/codenamecpp/carnage3d#other-gta-12-re-implementations
https://github.com/dtrajko/MoravaEngine
https://github.com/jmorton06/Lumos
https://github.com/Razakhel/RaZ
https://github.com/samdauwe/BabylonCpp
https://github.com/SasLuca/rayfork
https://github.com/Zylann/godot_heightmap_plugin
https://libregamewiki.org/Alexei:_Part_IX
https://libregamewiki.org/CameliaGirls
https://libregamewiki.org/Childish_Cannoneer
https://libregamewiki.org/index.php?title=Libregamewiki_talk:Community_Portal&oldid=25410#Some_long_term_ideas
https://libregamewiki.org/Libregamewiki:Suggested_games#Likely_sources_for_more_free_games
https://lichess.org/api
https://odr.chalmers.se/handle/20.500.12380/219006
https://osdn.net/softwaremap/trove_list.php?form_cat=80
https://pipoypipagames.itch.io/cows-revenge (https://github.com/Dariasteam/Cows-Revenge)
https://pixeldoctrine.com/index.html (more than just slime volleyball)
https://play.google.com/store/apps/dev?id=8387589286898375037 (where is the source, not open source otherwise)
https://playcanvas.com/
https://pyweek.org/4/entries/ (Ascent of Justice)
https://revolutionarygamesstudio.com/ Trhive
https://rpgmaker.net/engines/rpg20xx/
https://rpgmaker.net/games/2664/
https://salsa.debian.org/games-team/etw
https://scorched-moon.github.io/site/
https://scratch.mit.edu/ (https://en.scratch-wiki.info/wiki/Scratch_Source_Code)
https://senseis.xmp.net/?GNUGo
https://stendhalgame.org/wiki/Marauroa
https://verge-rpg.com/
https://voltisoft.com/miragelegacy
https://web.archive.org/web/20060411054656/http://home.gna.org/oomadness/en/index.html
https://web.archive.org/web/20060812164344/http://rubyforge.org/ (games from rubyforge)
https://web.archive.org/web/20170714065728/http://users.olis.net.au/zel/
https://web.archive.org/web/20171228172756/http://www.oletus.fi/static/whichwayisup/
https://www.adventuregamestudio.co.uk/
https://www.b3dgs.com/v7/page.php?lang=en&section=projects
https://www.babylonjs.com/
https://www.bennugd.org/
https://www.bsframework.io/
https://www.choiceofgames.com/make-your-own-games/choicescript-intro/
https://www.frictionalgames.com/forum/forum-28.html
https://www.glitchthegame.com/ (Glitch the game, by Tiny Speck Inc. public domain)
https://www.libretro.com/
https://www.musztardasarepska.pl/wgdown/
https://www.ness-engine.com/
https://www.old-games.ru/forum/threads/nekommercheskie-analogi-izvestnyx-igr.40868/page-9
https://www.piston.rs/
https://www.reddit.com/r/opensourcegames/comments/celw6c/top_3_open_source_pinball_games_2015/
https://www.scirra.com/construct2
https://www.seul.org/~grumbel/tmp/clanlib/games.html
https://www.tapatalk.com/groups/imperilist/
https://www.wurfelengine.net/
https://zdoom.org/downloads (gzdoom, lzdoom)
https://zope.readthedocs.io/en/latest/
https://github.com/QodotPlugin/qodot-plugin
https://github.com/gecko0307/dagon
https://github.com/open-telemetry/opentelemetry-cpp
https://github.com/googleforgames/open-match
https://github.com/hiitiger/goverlay