The Heroes of Olympus Series by Rick RiordanThis is Fine Print First Copy Similar to Original but not Original. The Heroes of Olympus series by Rick Riordan is an epic fantasy adventure that continues the world of Percy Jackson It introduces a new prophecy, seven demigods, and a rising threat from the Earth goddess, Gaia The story weaves together Roman and Greek mythology in a high stakes battle to save the world Percy Jackson returns alongside new heroes like Jason, Piper, Leo, Hazel, and