Chill of the Ice Dragon

In the ninth book, a Dragon Master named Mina arrives at the castle. She tells Drake and his friends that her kingdom in the Far North Lands was attacked by a magical Ice Giant. Everything there was frozen -- but Mina escaped! Only a fire dragon can unfreeze her land and defeat the terrible Ice Giant. But Rori and Vulcan are no longer at the castle! Can the Dragon Masters find them in time to help their new friend?