8 Kingdoms (https://sourceforge.net/projects/kralovstvi/, https://svn.code.sf.net/p/kralovstvi/code/): No license found
Aeron (https://sourceforge.net/projects/aeron/, https://svn.code.sf.net/p/aeron/code/): Very early development
Age of Magic (https://sourceforge.net/projects/ageofmagic/, https://svn.code.sf.net/p/ageofmagic/code/): Only supports outdated Hardware (Symbian)
Altera Terra (https://sourceforge.net/projects/alteraterra/, https://svn.code.sf.net/p/alteraterra/code/): Early development stage, no clear license information
Arthur's Knights (http://ainenn.org/KingArthur/, https://sourceforge.net/projects/king-arthur/): Unclear license, author could not be contacted
Atral Clades (https://sourceforge.net/projects/astralclades/, https://svn.code.sf.net/p/astralclades/code/): No clear license information
Begin2 (https://sourceforge.net/projects/begin2/, https://svn.code.sf.net/p/begin2/code/): No source available
Camelia Girls (https://web.archive.org/web/20140523011334/http://pigux.com:80/cameliagirls/): Sources not available
Cycle (https://sourceforge.net/projects/meegocycle/): Proprietary license (freeware, source available)
Drop Shock (http://www.tinywarz.com/index.php, https://sourceforge.net/projects/dropshock/, https://git.code.sf.net/p/dropshock/code): No license found
EarthShakerDS (http://simianzombie.com/posts/2011/05/10/earth-shaker-ds-released, https://github.com/ant512/EarthShakerDS.git): Target only Nintendo DS as hardware platform
Eleconics (https://sourceforge.net/projects/eleconics/): No license found
Entombed! (http://www.newbreedsoftware.com/entombed/, ftp://ftp.tuxpaint.org/unix/x/entombed/entombed-2007.07.04.tar.gz): Game very small
EXILE (http://forums.datarealms.com/viewtopic.php?f=82&t=19266, https://github.com/Geti/EXILE.git): Early development stage
Fight Or Perish (http://www.newbreedsoftware.com/fop/, ftp://ftp.tuxpaint.org/unix/x/fop/src/fop-0.5.tar.gz): Early development stage
Football Manager (https://github.com/autismuk/Football-Manager.git): Very early development stage
Free in the Dark (https://sourceforge.net/projects/fitd/): No source code available
FreeFT (https://github.com/nadult/FreeFT.git): All rights reserved.
Future Blocks (https://github.com/fogleman/FutureBlocks.git): Needs DosBox, simple Tetris clone (nice, but maybe too minimal)
Grow (https://sourceforge.net/projects/grow/): Insufficient content
Herzog 3D (http://herzog3d.sourceforge.net/, https://sourceforge.net/p/herzog3d/code/HEAD/tree/): Very early development
Homeworld SDL (https://github.com/aheadley/homeworld): Not open source compliant license (see https://github.com/aheadley/homeworld/blob/master/README)
imperialism-remake (http://remake.twelvepm.de/, https://github.com/Trilarion/Imperialism-Remake.git): Too minimal (I must know)
Jumping Jack 2 Worryingly Familiar (http://retrospec.sgn.net/game/jj2, http://retrospec.sgn.net/users/nwalker/jack/jjwf.zip): No compliant license found
Jumping Jack Further Adventures (http://retrospec.sgn.net/game/jj,  http://retrospec.sgn.net/users/nwalker/jack/jj.zip): No compliant license found
Jumpman (http://www.oldskool.org/pc/jumpman, http://www.oldskool.org/pc/jumpman/jump_src.zip): Only runs on DOS, License problems (taken without asking for permission)
KZap (http://kzap.sourceforge.net/): Very early development
LastNinja (http://lastninja.sourceforge.net/, https://sourceforge.net/projects/lastninja/): Early development, Abandoned, Needs original material that is probably not obtainable legally
legion (https://github.com/mahho/legion.git): No compatible license found
Lemmix (http://www.ericenzwaan.nl/eric/lemmings/lemmix.htm, http://www.ericenzwaan.nl/eric/lemmings/LemOpenSource.zip): Custom license, requires original content that is probably not obtainable legally
luminesk5 (https://github.com/kaikai2/luminesk5.git): No clear license information found. Not clear if runnable or if playable.
Manic Miner (http://retrospec.sgn.net/game/mm): Unclear license (freeware?), probably many from retrospec.sgn.net
Mining Haze (http://sourceforge.net/projects/mininghaze/): Very early development
MonoStrategy (https://monostrategy.codeplex.com/, https://codeplexarchive.blob.core.windows.net/archive/projects/monostrategy/monostrategy.zip): Early development (alpha), Not playable, requires original content, abandoned
Moopy (https://code.google.com/archive/p/moopy/, https://code.google.com/archive/p/moopy/source/default/source): Early development stage
New RAW (http://sourceforge.net/projects/newraw/, http://svn.code.sf.net/p/newraw/code/): Early development, requires original content, abandoned
Open General (http://www.open-general.com/, https://sourceforge.net/projects/opengeneral/, https://svn.code.sf.net/p/opengeneral/code/): Proprietary license (see credits.txt)
OpenDeathValley (https://github.com/OpenDeathValley/OpenDeathValley.git): No instructions, no releases, no website, not much code
OpenOutcast (https://sourceforge.net/projects/ocmod/): Very early development, no release, short svn history, abandoned
OpenPop (http://openpopulous.sourceforge.net/, https://sourceforge.net/projects/openpopulous/, https://svn.code.sf.net/p/openpopulous/code/): Very early development
openStrato (https://github.com/gerdl/openStrato.git): Not much code, no release or demo site, short code history, abandoned
pacman (https://github.com/snozza/pacman.git): Playable? We already have so many pacmans
Phavon (http://phavon.sourceforge.net/, http://phavon.cvs.sourceforge.net/viewvc/phavon/): Very early development
PKMN-FX (https://github.com/jonasdemoor/PKMN-FX.git): Code not available anymore
Project Diaspora (http://pdiaspora.sourceforge.net/): Proprietary license (see file headers)
Project: Xenocide (https://sourceforge.net/projects/xenocide/, http://xenocide.cvs.sourceforge.net/viewvc/xenocide/): Very early development
Promisance (https://sourceforge.net/projects/promisance/,http://promisance.sourceforge.net/): Went closed source with version >= 4.0
pyspaceinvaders (https://github.com/map0logo/pyspaceinvaders.git): Too small
PyTouhou (http://pytouhou.linkmauve.fr/,http://hg.linkmauve.fr/touhou): Sources not available anymore
Racer (http://racer.sourceforge.net/, http://sourceforge.net/projects/racer/): Very early development, Inactive
Ruby OMF 2097 Remake (http://rubyomf2097.rubyforge.org/, svn://rubyforge.org/var/svn/rubyomf2097): No source code found, web site offline
RuneSword II (https://sourceforge.net/projects/runesword/, http://runesword.sourceforge.net/, https://github.com/mattiascibien/Runesword.net, https://github.com/aceofspades19/Runesword-II-OS.Net): No license found
sCoreForge Pathfinder Character Creator (https://sourceforge.net/projects/scoreforge/): No license found
Scoreus (https://web.archive.org/web/20120618143653/http://scoreos.org:80/about, https://code.google.com/archive/p/scoreos/, https://github.com/Lozza999/scoreos.git, https://code.google.com/archive/p/scoreos/): Source code not found
Snipes (https://www.vogons.org/viewtopic.php?f=7&t=49073, https://github.com/Davidebyzero/Snipes.git): Not open source as in free, copyright retains with the authors
Sokoban (https://sourceforge.net/projects/sokoban/): Proprietary license
Solar Empire (https://sourceforge.net/projects/solar-empire/, https://git.code.sf.net/p/solar-empire/code): No license found
Solaris (https://sourceforge.net/projects/solaristhegame/, https://svn.code.sf.net/p/solaristhegame/code/): Very early development stage
Space Station 14 (http://www.spacestation14.com/): Offline, contains no clear game
Spaceship Duel (https://archive.codeplex.com/?p=spaceshipduel, https://spaceshipduel.codeplex.com/SourceControl/latest): Cannot download archive from codeplex
Starlane Empire (https://gna.org/projects/starlane/, http://cvs.gna.org/cvsweb/starlane/?cvsroot=starlane): No sources available, see issue #18, gna.org lost
Styx (http://retrospec.sgn.net/game/styx, http://retrospec.sgn.net/game-links.php?link=styx): Unclear license information, not open source in our sense, see other entries from retrospec here
Super Mario Bros With SFML in C# (https://mario.codeplex.com/, https://mario.codeplex.com/SourceControl/latest): Codeplex cannot access archive, therefore no source, might be just a previous state of Mario Objects
Sworsorc (https://svn.code.sf.net/p/alteraterra/code/): Proprietary license (copyright headers in files)
thromolusng (https://github.com/segfaulthunter/thromolusng.git): Very early development, not playable, no build instructions, abandoned since 2010
Tranzam (http://retrospec.sgn.net/game/tranzam, http://retrospec.sgn.net/download/files/TranzAm.1.1.zip): see other retrospec.sgn.net entries, license unclear, probably not open source as we want it
VegaTrek (https://sourceforge.net/projects/vegatrek/, https://svn.code.sf.net/p/vegatrek/code/): Unclear licensing, copyright of assets questionable
Visions from the Other Side (http://www.insani.org/mukou.html): Source not available
Voxelstein 3D (http://voxelstein3d.sourceforge.net/): Very early development
WarGame (https://archive.codeplex.com/?p=wargame): Unclear license, could not contact authors