Here are some FLOSS/FOSS gaming–related official fediverse accounts (as listed on their official website(s)).
(in alphabetical order)
I. Game manager and playtime tracker
* Lutris — @lutris
II. FPS (First–person Shooter)
* Unvanquished (mix RTS+FPS) — @UNVofficial
III. MMOG (Massively Multiplayer Online Game)
* Crossfire — @crossfiremrpg
IV. Platformer
* SuperTux — @supertux
V. RTS (Real–time Strategy)
* 0 A.D. — @play0ad
VI. Sandbox
* Minetest — @Minetest
VII. Sim / Simulation
* OpenTTD (transport) — @openttd
* Simutrans (transport) — @simutrans
* Speed Dreams (racing) — @speed_dreams_official
VIII. TBS (Turn–based Strategy)
* FreeCiv — @freeciv
IX. TBT (Turn–based Tactics)
* The Battle for Wesnoth — @wesnoth
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Meta:
* Games list source: https://en.wikipedia.org/wiki/List_of_open-source_video_games
* Tags: #gameshogun #Gaming #Games #Game #Gaming #Fediverse #FreeCulture #FLOSS #FOSS #OpenSource