Ruins & Revenge - A Raine Benares World Novel, #9

An ancient power. Beneath a mountain on an uninhabited continent is said to be a fabled city, a city occupied by an ancient goblin civilization founded for only one reason-to protect and defend the Heart of Nidaar, an artifact that can harness the forces of nature as a weapon. An elite team of combat mages. Chief mage and goblin duke Tamnais Nathrach must help the guardians keep the legendary power out of the hands of a malevolent goblin brotherhood and their otherworldly allies, whatever the cost.
Together with his hand-picked team-which includes elf pirate (and team demolitions expert) Phaelan Benares-Tam descends into a vast subterranean world both wondrous and terrifying, a world laid with deadly traps and filled with apex predators from another age. The countdown to the end of the world. Some secrets are meant to stay buried. When the Heart of Nidaar is accidentally awakened, and aimed at the west coast of the Seven Kingdoms, Tam and his team are in a race against time to prevent the deaths of millions.
To succeed, they must confront their deepest fears, unmask their darkest secrets, and reveal their shameful pasts, testing the bonds of friendship and beyond. To fail means death for them all-and the end of all life in the Seven Kingdoms.