This was a phenomenal addition to the grisha universe. I really loved exploring the characters we had some familiarity with. I especially appreciated getting a deeper glimpse of Zoya. Not only did we see her past and what brought her to where she was, but we also got to see her experiences during shadow and bone, which expanded those events in an interesting way. Not only that, we got to see more of Nikolai and how he became the man he is. I loved their relationship and the way that they cared for each other. I liked Nina's plotline as well, although it didn't engage me as well as the other. I think this was most likely because she really had to grow past her grief in order to find what she was meant to do. Not only was this hard because I was still feeling the pain from the end of Crooked Kingdom, but also because it slowed the progress of the action. I really liked the development of Nina's character though and the way she grew to accept her own power. I really liked how the story added tidbits and easter eggs from the previous books. I also think the twists were really captivating, which is something Leigh Bardugo does very well. Each one is set up in little ways, so when it happens you feel like you should've seen it coming, but they aren't so obvious so that you do. One of the only issues I had was the use of parallel storylines. Usually, that's something in books that I don't like, it tends to cause pacing issues and takes me out of the story when I'm just getting into it. This book did a good job avoiding these things, however, it ended without bringing these storylines together. It left me kind of confused as to why there were two plot lines included at all. At the end of the book, it seemed like they were being set up to come together more in the following book, but I wished there would have been more of a connection made. Overall, I think this is one of Leigh's best works and I cannot wait to finish this duology.