Another vote for God Emperor. For me, it was a bit overwhelming on first read, but I love that I can keep going back to it. The ones I reread the most (and prob

Another vote for God Emperor. For me, it was a bit overwhelming on first read, but I love that I can keep going back to it. The ones I reread the most (and probably consider the most mind-expanding) are Dune, God Emperor, Heretics, and Chapterhouse.