Transcendence and Rebellion. The Riven Gates, #3

The world is on the cusp of destruction as Mordecai's power grows beyond the limits of his own control, yet most of the powers that rule the world are oblivious. The only hope of salvaging their civilization lies with his children, but they have been scattered and branded outlaws. Meanwhile Tyrion continues to march toward his own goals, heedless of whether they will help or harm their efforts to stop the apocalypse, as even the Queen begins to doubt the archmage's sanity.
Mordecai is trapped by his own strength, a power too great to wield. Can his children stop the end of everything, even if it means sacrificing their father?