This book. Brigid Kemmerer has never failed to make me cry, scream into my pillow, throw the book across the room, punch my mattress, have to stop reading out of shock and just adore/loathe her characters. 
Jax was such a well rounded and intriguing new member of the cast, Callyn I had mixed feelings about until the very end when I decided I adored her, and of course it was wonderful that Tycho my beloved was given a POV in this story. (I will be extremely mad if he or Jax don't get POVs in the next one.)
I love how the relationships in this story added to the ones already established in the cursebreaker series, and I was glad to see Rhen back to his scheming. Jax and Tycho were so gloriously domestic and Lia Mara's bond with Callyn was really comforting to read.
My only issue(?) with this book was likely the lack of racial diversity. As much as Kemmerer has written some of my favourite characters of all time, only Noah (I think) is a canon POC main in her fantasy work. I would love to see more racial diversity in these stories.
Overall, however, for sure a new favourite.
EDIT - this is also the first book I’ve read in ages which I consistently read 100+ pages each time I picked it up, which is just huge credit to Brigid’s writing.