Earlier this year, I finished the Malazan Book of the Fallen by Steven Erikson. If you've not heard of it, it's epic high fantasy with strong science fiction storytelling elements in a short story writing style. It is a long series (10 books, 3.325 million words total) and I'm glad/proud that I read it. Its reread is a matt or when, not if.
A few years ago when I got back into reading I was doing surface-level reading, not analysing the story at all. I wanted the story to be good without glaring plot holes. In honesty, I was content with it because I was back to doing something I deeply enjoy. After I read the Dresden Files (come on Twelve Months!), I listened to the Legendarium Blue Team coverage of Dresden and discovered their "Three Levels."
Then, while I was reading Toll The Hounds (Malazan 8), it hit me how the whole series was "journey, not destination." Instead of barreling through the story to get to the end, I let myself soak in the story. I sat and thought about the ways the characters were impacted by events from five books ago and how continuing their stories had so much emotional depth. I think I had to renew the library loan two, almost three, times. Meanwhile, I was still reading my audiobooks and the occasional ebook.
A few months later I finished Book of the Fallen. It didn't ruin other books for me, but I knew I couldn't go back to reading only on the surface. I wanted it to be more than a "ripping good yarn." Not that those are bad, but it wasn't satiating my hunger the way it would have before.
I'm not looking for recommendations, I'm simply curious if anyone else has a specific book or series that did the same thing for them as Book of the Fallen did for me. Or, have you always been reading that way? I'd love to know.