Draconis' Bane (Blood Feud Book 1)

Dragon magic has faded from the lands of the Seven Kingdoms and the power they exercised over the elements has failed. Already Terum has reverted back to being covered by volcanic ash and great storms destroy ships and palaces alike all over the largest continent.
Prince Tristan Vallious is born into this uncertain world and not unlike many children of royalty, he's arrogant and abusive. The King and Queen have no choice but to send him to the border under the command of his older brother. There he can work out his issues while defending his country against all kinds of creatures, both men and other of a less savory sort.
Before he can assume his new post, he is attacked by a magical assassin, placing him in a coma. The Nightmare Spell used is a terrible fate and most die within a week of being plunged into their own worst fears, losing the will to live quickly. Tristan now stands at a crossroads and the weight of the world of both men and dragon rest on his shoulders.