How to Break a Dragon's Heart 

Stranded on the exceptionally dangerous, and possibly haunted, Beach of the Broken Heart, Hiccup must face UG the Uglithug and complete the impossible task -- or die trying. Along the way, he'll have to battle Berserks, dodge Scarers, and save Fishlegs from being fed to the Beast, all while being hunted down by an old enemy with a dark secret about the mysterious Lost Throne. With Toothless by his side, and time to stage his rescue running out, what's a Hero to do?