The Skeleth / Matthew Jobin.

Enhanced descriptions from Syndetics:

For the lords of the north, land is power. The Nethergrim, now awoken and free to wreak its evil upon the world, offers the promise of victory to those ruthless enough to accept its foul bargain. One ambitious lord, eager for the chance to conquer and rule, succumbs to temptation and helps to free the Skeleth-eerie, otherworldly beings said to be unstoppable in battle. The Skeleth merge with the bodies of their victims, ruling their minds and turning them into remorseless killers. Worse yet, to kill the man inside the Skeleth only frees it to seize a new host, starting a cycle of violence that has no end.

Such chilling tales are not enough to stop young Edmund, innkeeper's son and would-be wizard, from seeking for a way to turn back the oncoming tide of destruction. Along with his best friends-Katherine the trainer of war-horses and Tom the runaway slave-Edmund searches for a magical weakness in the Skeleth, something that might allow him to break their never-ending curse. The three friends join with the legendary hero Tristan in a battle of courage, wisdom, wits, and sacrifice to stop the Skeleth from ravaging their homeland and all they hold dear.

This adventurous tale that marries earthly greed to otherworldly evil is perfect for fans who enjoy the epic worlds of John Flanagan's Ranger's Apprentice, Robert Jordan's The Wheel of Time , J.R.R. Tolkien's The Lord of the Rings , and George R.R. Martin's Game of Thrones . Discover for yourself why so many are making the comparisons!