This was the best one yet! This series will forever live rent free in my head. I'm so glad that we get a 5th book to find out more about what happens next for the group. 
I love how everyone developed in this one, and we finally got answers to all the questions popping up throughout the last 3 books with Keira gaining her memories, finally meeting the face behind Aztec, seeing firsthand how Daisy plays into everything, and seeing how powerful Keira can be.