Oath of Vengeance The Hidden Archmage

After sealing away a black dragon, a legendary wizard loses his father and must live three years with his magic sealed. As a school librarian he quietly watches over his younger brother while enduring ridicule. When a rival academy turns a tournament deadly, he steps forward to protect the students. As the seal expires his power returns, and he must save his allies, uncover the truth behind his father's death and reunite with his brother against the forces of darkness.