This was really interesting. There's fantasy, science, a smidge of romance, mystery horror and history. Its only YA because the main characters are teenagers but it doesn't focus on that. The horror can be pretty horrifying but its mostly blood and gore. This was so well written.

Just FYI you want get any clue as to what's going on until around page 300. I read this as part of a book club pick and I knew going into it it was going to be unlike anything I've ever read and that is the truth. But the blurb sounded interesting. There is some fantasy-like world building which is often mind-blowing. So much terminology that I struggled to grasp what was going on, which I like. This book made me work to understand it and I appreciated that. Usually I go for complex characters and detailed imagery but the complexity in this was in the world itself. And its not over, this is only book one and the characters have just figured out the basics of this world when they get thrust into the new one that will be the focus of the next book. I'm going to give my brain a break before I read The Dark Passages though.

I honestly don't know what else to write without any spoilers so I'll leave it there.