Search free PC games by operating system

I decided to fill Free Games Utopia with all kinds of video games developed for desktop platforms — from lesser-known MUDs and text-only interactive fiction to massive MMOs and classic platformers. The result is a constantly growing database of free games for every existing PC desktop operating system (Windows, Linux, macOS, etc.) as well as some long-retired ones, like Amiga, Commodore 64, and MS-DOS.