I really enjoyed the characters, particularly the female characters. Both Merrin and Susan were both just really well rounded characters and I loved how loyal they were to their cause. The rivalry between Tom and Mason really added to both of their character as well.
While I did really enjoy all the specifics of the premise, I never completely fell in love with the story line. There were some parts I just wanted to be pushed a little further. Dan Krokos's world building is completely solid - the way he incorporated magic and the different galaxies was really neat.
There are super cool sketches throughout the book which really add to the story. They helped to solidify what these different elements and beings Dan Krokos introduces in the story.
While this one was not as strong as Dan Krokos's YA series, I still thought it was a solid start. I loved the high stakes throughout the book and the fact that he doesn't offer security to anyone really.