My favorite low spec gaming setup is to load Xonotic on the shittiest computer I can find just to see if I can actually find a computer lowspec enough that it actually starts struggling with framerate.

I am not sure it is possible without resorting to some old ass computers or a raspberry pi (which still might run it ok lol idk).

Also during the periods I haven’t had access to a computer that I could play actual games on I end up playing a lot of Cataclysm Dark Days Ahead because it is one of the most amazing games ever and it will run on pretty much any computer period.