The Executioner's Daughter — Miguel Conner

For millennia, the stark Kingdom of Keloveria has thrived in a bleak, hostile world of ageless horrors and ripe threats. Its survival is largely dependent on two ancient, sentient relics -- the crown Forethought and the axe Afterglow -- worn respectively by the king and his executioner, Deadspeaker. The king judges the living and Deadspeaker judges the condemned. In their parity, order flows throughout the Misty Continent and even in unearthly realms.
Then the youthful Tendrik Partaghast is newly crowned, while the aging executioner Mateoz knows his time grows short. The balance of power is suddenly tilted when the Deadspeaker breaks the covenant with mankind by choosing his own newborn daughter as the successor of Afterglow. This unprecedented heresy sows the seeds of revolution from long-resentful royal Houses and an opportunistic clergy. Worse, the broken pact invites foes in the form of arcane necromancers, barbarian hordes, and forgotten gods. Heroic forces also arise to counter the emerging bloodshed and chaos, most notably a long-banned knight class led by Aron Durmyr, the Knight of Swords.
The ambitious yet untested King Tendrik realizes that a shift of ages has arrived and begins his own machination, not least to eliminate the executioner's child... King and Deadspeaker are drawn into the same esoteric rivalry between Forethought and Afterglow that has raged since the beginning of time.
But in this cycle, the reign of mankind might come to one, final end…