Basically Ocean's Eleven set in the fantasy alternate universe of the Grisha trilogy. 
 Really solid heist novel, I enjoyed it very much and will definitely read the sequel! My only gripes: 
 1) the protagonists are literal children which just... doesn't fit their characters? You've got those world-weary, life-hardened criminals and they're... sixteen... What. I kept laughing everytime their ages were mentionned. I mean I realise this is a fantasy book but my suspension of disbelief doesn't stretch that far. 
 2) This is a matter of personal taste but I don't enjoy romance, I pretty much always find it tedious and there is. so. much. of it in these pages. Caveat emptor, I guess.