For the old timers who want a shot of super nostalgia the Internet Archive has made a lot of the old games available.
https://archive.org/details/softwarelibrary_msdos_gamesWho can forget the old Empire game? That was my first strategy game I think, although I played a version with satellites that was super fun.
https://archive.org/details/msdos_Empire_Deluxe_1993