Stone Quest! The Wrath of the Dragon King (Dragonwatch) by Brandon Mull

Behind him, dragons roared. As he slipped into the little cave, Seth's last glance show the tentacled dragon rising. He kept still, holding his breath, pressed back against the rear of the cave. "Come OUT!" a slithery voice called. "I saw you enter, Caretaker. Surrender!"

A head snaked into cave, mostly filling the tunnel. Seth felt fear, but he slashed his sword through the grasping tentacles, severing at least four. Ichor fountained. "For Kendra," Seth murmured.

"You die now!" the dragon declared. Seth held his sword ready. Suddenly the head flopped to the floor and stopped advancing.

"Hurry, boy!" a deep voice boomed. "I'm your Dragon Slayer!" It was the Somber Knight.

"A dragon ate Kendra," Seth said, surprised that he could spit out the dreadful words.

"No," the Somber Knight said. "Your sister lives."

Seth and Kendra, young Caretakers of Blackwell Keep, guardians of all the fairyfolk and magical creatures who have taken refuge there, have had an invitation they couldn't refuse, an invitation from Celebrant, the fearsome Dragon King, to a Feast of Welcome. The dragons are revolting against confinement in their sanctuary, eager to break out to control the known world, and Seth and Kendra, child caretakers of the domain of Wyrmroost, scarcely trust the safe passage promised by the dragons while traveling to Celebrant's Feast. But to refuse the invitation is to be summarily attacked, so with a promise of a sacred truce during the Feast, the two children fly to the dragon's lair on griffon back. But the fears and warnings of their friends come true. Celebrant provokes a confrontation with his most deadly rival for the Dragon throne and after a gory and grisly battle, announces his war on all the Protectorates--Terrabelle, Zowali, Gundertan, Herdlands, the Sludgeholes, and of course Wyrmroost.

Their trusty griffons slaughtered by the dragons, Seth and Kendra survive a near-death experience in the perilous journey back to Blackwell Keep, realizing that they must lead the resistance to Celebrant's dragon army to save their world. Seth learns that the secret to overpowering the Dragon King is the legendary Wizenstone, concealed within the remote and cursed Stormguard Castle. Accessible only on the festival nights of the solstices and equinoxes, it is a place where all, even dragons, must appear human form and no magical powers may be used. But to find their way to the Castle, the two must have the help of the powerful fairy Rivenmay.

Because she is Fairykind, Kendra is chosen to traverse the Bewilderness, a place where only those things which appear most wrong are right. Kendra finds Rivenmay and gains her aid, and now she and Seth must confront their deadly rivals inside Stormguard and outwit them in the quest for the sacred Wizenstone to save their world from the dragons' wrath.

For young readers who love sword and sorcery fantasy, Brandon Mull's second in his Fablehaven spinoff series, Wrath of the Dragon King (Dragonwatch) (Shadow Mountain, 2018) has the fantastic in spades. Mull's Dragonwatch world contains fantastic creatures known and heretofore unknown and a convoluted plotline with more twists and turns than a dragon's tentacles. Young dragonslayers will journey gladly through as bizarre and yet familiar a world as that of J. R, R, Tolkien, a place where the savvy who are willing to suspend disbelief will find their home.

The best-selling Brandon Mull's first book in this series is Dragonwatch: A Fablehaven Adventure.