I miss when games used to provide giant reams of text like that. There was a game, "Lords of Magic" that came with, essentially, a small novel's worth of entirely superfluous setting information (in the form of a little book!). It had the kind of background fluff you'd normally find in a D&D manual. I think I spent about as much time with the book, as with the game.

It's playable on any common desktop OS via OpenMW (you'll need a copy of the game for the art, level data, sounds, et c, though), which is also far more stable than the official binary, and has some nice QOL improvements baked in.

If Alpha Centauri's concept of parallel colonization by a group of rivalrous and ideological charismatic leaders is explored in a book as well, I bet that would be fun.

[1] https://www.goodreads.com/series/129586-the-pandora-sequence

"THE JESUS INCIDENT Frank Herbert

A speculative and philosophical tour de force by my favorite science fiction author. You’ll probably have to search used bookstores for this one, but it’s well worth it. My favorite science fiction novel ever. A clear inspiration for the story of Planet."

That manual is quite something! Moon comparisons, a long short story, tons of background material on each attribute of the planet...

[1] https://slatestarcodex.com/2016/04/27/book-review-albions-se...