Dragon Spear by Jessica Day George
With peace established between the humans and the dragons, young couple Creel and Luka are planning their wedding. But then the dragon queen, Velika, is kidnapped by a band of rogue dragons in need of a ruler. When Creel and Luka rush to help, they discover that Luka’s father has plans to take back the Far Islands from the dragons. Creel’s happily ever after just might be postponed . . . again.