The Son of Neptune: The Heroes of Olympus, Book Two

In The Lost Hero, three demigods named Jason, Piper, and Leo made their first visit to Camp Half-Blood, where they inherited a quest:

Seven half-bloods shall answer the call,
To storm or fire the world must fall.
An oath to keep with a final breath,
And foes bear arms to the Doors of Death.

Who are the other four mentioned in the prophesy? The answer may lie in another camp miles away, where a new camper has shown up and appears to be the son of Neptune, god of the sea.

• The Mark of Athena: The Heroes of Olympus, Book 3
• The Heroes of Olympus, Book One: The Lost Hero
• The House of Hades: The Heroes of Olympus, Book 4
• The Blood of Olympus: The Heroes of Olympus, Book 5
• The Last Olympian: Percy Jackson and the Olympians, Book 5
• The Battle of the Labyrinth: Percy Jackson and the Olympians, Book 4
• The Titan's Curse: Percy Jackson and the Olympians, Book 3
• The Trials of Apollo, Book One: The Hidden Oracle
• The Sea of Monsters: Percy Jackson and the Olympians, Book 2
• The Dark Prophecy: The Trials of Apollo, Book 2