Rumblestar

Eleven-year-old Casper Tock, who dislikes risks and adventures, accidentally enters Rumblestar, an Unmapped Kingdom filled with magical creatures. There he learns that Rumblestar is threatened by an evil harpy, Morg, who wants to steal its magic. Casper teams up with Utterly Thankless and her dragon, Arlo, to stop Morg and save both the Unmapped Kingdoms and his own world. Together, they face various magical beings in a quest to protect the magic of the Unmapped Kingdoms in this new series by Abi Elphinstone.