The Skull Throne (Demon Cycle, #4)

"The Skull Throne of Krasia stands empty. Built from the skulls of fallen generals and demon princes, it is a seat of honor and ancient, powerful magic, keeping the demon corelings at bay. From atop the throne, Ahmann Jardir was meant to conquer the known world, forging its isolated peoples into a unified army to rise up and end the demon war once and for all. But Arlen Bales, the Warded Man, stood against this course, challenging Jardir to a duel he could not in honor refuse"--Dust jacket flap.