I was going to say replaying but I feel like that limits the question to games like Prey or Fallout New Vegas that have endings and games like The Sims 2 or Cities Skylines where you can play indefinitely end up excluded.
I’m not really referring to games like League of Legends where you’re coming back every month. More so games where you stop playing for an extended period of time.
Fallout 4 and FO:NV
Civ VI
The entire Myst series, Obduction (haven’t played Firmament yet)
Ultima VII, Ultima Underworld, Ultima Underworld II
Beneath a Steel Sky, Beyond a Steel Sky
Is there a third game in the series I’m not aware of or did you mean Beneath a steel sky?
I did mean that. Fixed
Ooh, Under a Steel Sky. I’ve been in the mood to play one of those old ScummVM games. How is that one?
Great story. It’s on GOG. Beyond a Steel Sky is the sequel, released a few years ago. Kinda sad, but really great, too. Made by the creators of the original from the 90s, and has an in-game commentary track!