The Mage's Grave: Mages of Martir Book #1

Thirty-five-year-old Darek Takren always did his best to keep up with the demands of the prestigious North Academy, a magical school where only those with the drive to succeed are allowed to learn. Having lived in the school for his whole life, Darek Takren sees North Academy as his home, a sanctuary safe from the troubles that plague the outside world.
But when his best friend is injured in an unexpected attack on the school, Darek Takren struggle to uncover the attacker's identity leads him into a much deeper scheme that, if successful, will spell the end not only for the school, but for the whole world and the gods themselves.
And he may not have what it takes to stop it.