Iskandar. Michael F. Bird

Set in the mystical kingdom of Iona, a young slave boy named Iskandar learns that he is the son of the King and Queen of Iona, once noble rulers who were seduced by the dark Lord Marduk with a promise of divine power. Iskandar discovers what happened to his family, how he was hidden from his parents by his uncle, the secret power he has that even his immortal parents are afraid of, and the obsessive determination of his elder brother Jakov to use him as an instrument of revenge. Iskandar must travel through forests filled with dangerous creatures, fight battles against impossible odds, draw on the help of a mysterious knight, and learn to use his elemental powers, all while being constantly haunted by the question of whether he really has the courage to confront and even kill the immortal king of Iona, his own father.