Michael Pryor 
Chronicles Of Krangor 1: Lost Castle 

A classic fantasy quest — with an exciting dinosaur twist — from the creator of the Laws of Magic series and the Quentaris Chronicles.When Queen Tayesha threatens to conquer all seven kingdoms of Krangor and thus break the ancient bond between the saur and the land, one young noble vows to stop her. Adalon’s promise sets him on a perilous quest. He and his loyal friends, Targesh and Simangee, must find a safe haven, far from the queen’s bloodthirsty soldiers. Beyond a river of fire, a lost castle beckons. Mysteries and magical wonders await the three friends at the castle — but awakening ancient magic brings its own dangers.