The Heroes of Olympus
"The Heroes of Olympus" is centered around a prophecy, introduced in "The Last Olympian", that predicted seven demigods would unite to protect the world from an awakening new enemy, Gaia. Demigods from both the Greek camp, Camp Half-Blood, and a newfound Roman camp, Camp Jupiter, unite to save the world from being destroyed by the terryifying Earth Goddess, Gaia. The prophecy reads: