Just tell me, Percy, do you still have the birthday gift I gave you last summer?" I nodded and pulled out my camp necklace. It had a bead for every summer I'd been at Camp Half-Blood, but since last year I'd also kept a sand dollar on the cord. My father had given it to me for my fifteenth birthday. He'd told me I would know when to "spend it," but so far I hadn't figured out what he meant. All I knew that it didn't fit the vending machines in the school cafeteria.
Rick RiordanThere!" Mars finished writing and threw the scroll at Octavian. "A prophecy. You can add it to your books, engrave it on the floor, whatever." Octavian read the scroll. "This says, 'Go to Alaska. Find Thanatos and free him. Come back by sundown on June twenty-fourth or die'." "Yes," Mars said. "Is that not clear?" "Well, my lord...usually prophecies are unclear. They're wrapped in riddles. They rhyme, and..." Mars casually popped another grenade off his belt. "Yes?" "The prophecy is clear!" Octavian announced. "A quest!
Rick Riordan