The Whisper of Bones. The Banished Legend, #3

After a deadly attack on one of Ornala's greatest settlements leaves not only the country in disrepair, but one of Odin's friends dead, there seems little left to live for. Grief-stricken and out of his mind, he flees the kingdom with his eyes set on discovering the true meaning of Death from the Elves. Along the way, he befriends a Halfling who leads him through the Elven forest. There, Odin is taken under the wing of a creature whose vast magical knowledge leads him toward the discovery that may change his life.
The Elven Book of the Dead, written and created by the infamous Dark Elves, promises a reward Odin can only dream of. There's only one problem. Hidden within the depths of the Elven castle and guarded by the greatest of magics, it will take a feat of willpower unlike anything Odin has ever attempted to secure the book. With nothing left to lose, Odin must make a choice: to return home and begin life anew, or to risk the greatest magical offense in human history to bring back the important person in his life back from the dead.