This list was given to me by @lelkins@lemmygrad.ml on the genzedong.xyz matrix server
shoot games:
xonotic - quake-like with pretty nice graphics. uses a heavily modified version of the quake 1 engine, and it still looks very nice
openarena - quake 3 with free assets. compatible with most, if not all quake 3 mods
red eclipse - a really fancy foss fps game with parkour elements! hats!
freedoom - doom 1 and 2 but fully clean from copyright. the music slaps.
mega man 8-bit deathmatch - a doom-based arena shooter game. i consider this open source because it's made with open formats like wads and pk3s, and the developers actively promote modding of the game... and because it uses zandronum. zandronum's foss.
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minetest:
minetest (now known as luanti for that 5.10.0 version) - minecraft if it was epic. shaders built-in. mod support from the start. many great games. IT'S MINETEST. REALLY NICE STUFF, HONESTLY.
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strategy games:
openra - if you have assets from red alert 1, you can play red alert through this, even with multiplayer!
openhv - free and open source strategy game that uses the openra engine. based on a scrapped game with the graphics done by the guy behind opentyrian
unciv - civ 5 but libre, with mod support and multiplayer
mindustry - very good real time strategy game similar to factorio but with waves and stuff. another good game that i tried before knowing about foss stuff
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platformers:
sonic robo blast 2 - most say it's the best sonic game in general. oldest sonic fangame that still gets updates and uses a heavily modified doom engine. holy fucking shit, it's so good. under the gpl licence
supertux - you know super mario world? this is like mario but with speed. and tux.
super mario bros x - the classic mario fangame engine created by redigit. yes. the terraria people. AND IT'S OPEN SOURCE. THE WAY TO PLAY IT ON LINUX IS "THEXTECH", IT'S REALLY GOOD!!!
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racing games:
supertuxkart - the most mario kart-like game around. you can play as tux... and the xfce rat. i like the xfce rat
dr. robotnik's ring racers - i talked about this game. highly recommend, feels like a full game. more chaotic than any mario kart out there
sonic robo blast 2 kart (srb2kart) - older version of ring racers. made more for multiplayer and less complicated, still pretty good. most likely more active compared to ring racers btw
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top-down shooter games:
opentyrian - classic shmup known as "tyrian 2000" is in the public domain! the creator of the assets helped with openhv! it's so good!!!
powermanga - i put this here for the funny name. it's ok, imagine galaga. it's like galaga
taisei project - it's touhou. i can't play touhou. not even easy mode. have fun. it's even in your web browser too.
there are more foss roguelikes because the entire genre was grown up with foss
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shattered pixel dungeon - the nicest game on mobile. one of the first foss games i have ever played. also on pc. i played it on so many trips and waiting lines, holy shit
doomrl - wanna play doom in a turn-based roguelike way? this is it. graphics made by the guy behind spelunky
spelunky classic - made by the guy behind spelunky. source code released by the guy behind spelunky. there's "spelunky classic hd" that makes the game playable in widescreen
dungeon crawl stone soup - classic rogue experience. get the orb of zot cause i can't. very chaotic too
cataclysm: dark days ahead - rogue but with zombies. and a lot more.
nethack - one of the oldest roguelikes around. still worked on. holy fucking shit
witch blast (it's isaac with wizards!!)
there are so many
