Prophecies in The Son of Neptune

In book two of the Heroes of Olympus series The Son of Neptune during the war games Frank Zhang is claimed by Mars and given a prophecy which was just really just a sentence telling them what they already knew.

"Go to Alaska. Find Thanatos and free him. Come back by sundown on June twenty-fourth or die."

Two lines of the actual prophecy is also recited to Frank by Ella the harpy while the trio is visiting the Zhang Mansion is Canada.

 "To the north, beyond the gods, lies the legion's crown. Falling from ice, the son of Neptune shall drown-"