Mythborn II: Bane of the Warforged: Fate of the Sovereign, Book 2

Set against the epic backdrop of a world at war with myths and legends brought to life, Mythborn 2 continues the sweeping saga of Arek Winterthorn, wayward apprentice of the eldritch Way as he struggles to survive in the demon realm of Arcadia. Accompanied by Prince Niall Galadine, he searches for his father, unaware he is the prize in a war between Highlord Valarius Galadine's warforged elves and Lady Lilyth's demonic Furies. One seeks to possess him, the other to use him as a weapon as something dark and sinister within him grows, something called - blackfire.
 

Behind all this lies Sovereign, the maker and unmaker of worlds, waiting to see who will win, and who will die.