I love Endless Sky, it’s honestly one of my favorite games! I have a pack of cool SciFi art that I found on Nexus and I’ve been slowly replacing the stock photos for my personal game. I’m also a sucker for TeeWorlds, it is delightfully infuriating and hillarious to play. I know that’s baby’s first FOSS games but I’m new to open source games. That’s why I want to hear your recommendations and see what are some other good ones out there.
I love SuperTuxKart! I really like the user generated content, I had a mod that let me play as the F-Droid character. I ended up having a whole cast of FOSS mascots that aren’t in the base game.