The King's Head — Susan Price

Then the lantern, swinging from his hand, shifted its light. The Monk expected to see the glint of a chain-mail coat, or the dull buff of a leather jacket sewn with iron rings. But there was nothing below the head...Wandering the grim battlefield, Brother Dominic is overjoyed to hear a voice, calling him. Perhaps there is one more poor soul left alive in all this devastation. He hurries to aid the injured warrior, prepared to do all he can to keep this last survivor in the land of the living. But nothingcan prepare him for what he finds...From warrior-bard to disembodied head in one sweep of a sword-just what is keeping Egil the storyteller alive? And what exactly is he planning?