i didn't like the fifth one much either, though that may just be because it takes the sad but funny acceleration/power creep of stupidly impossible technology like bistromath, time travel, and (AI assisted!) multiverse time travel to its conclusion, it all stops feeling special, or because the only thing all this does to problems of capitalism (the cathedral of chalesm) and other human problems is make it more absurd (for comedic effect). idk i still left out like more than half the reason further books in the series feel more depressing than earlier ones, as I don't know it. Why is it a trilogy?