From the creator of Percy Jackson heroes of Olympus the son of Neptune is the second series . One cursed demigod you new heroes.A quest to unleash the god of death.... 'I'm the god of Rome .I protect the legion s I don't want war without end . You will serve me.'. ' Not likely,' Percy said. 'I order a quest !' rmyhe god announced. You will go north and find Thanatos in the land beyond the god .You will free him and thwart the plans of the giant .'