The Last Olympian
Rick Riordan
 In order to try to head off Kronos' approach by sea, Percy and Beckendorf attempt to destroy his ship, the Princess Andromeda. However, Kronos, still possessing Luke Castellan, is not caught off guard, and Beckendorf sacrifices his life to destroy the ship, while Percy dives overboard and passes out from contact with Kronos' scythe when battling him on the ship. Percy is awakened by his half-brother Tyson, the cyclops. He finds that he is in his father Poseidon's underwater palace, which is under siege by the forces of the Titan Oceanus. Percy wants to stay and help fight with his father, but Poseidon sends Percy back to Camp Half-Blood. At Camp Half-Blood, Chiron decides it is time for Percy to hear the "Great Prophecy." Percy informs the camp that there is a spy among them, someone who has been informing the Titans for years, but they put it aside until the bigger issues at hand are dealt with, such as the impending war against Kronos. Soon after arriving, Percy leaves again with Nico di Angelo, son of Hades, to find out Nico's plan for Percy to survive the battle, as mentioned at the end of The Battle of the Labyrinth. After visiting Luke's mother in Westport, Connecticut, and talking with Hestia, goddess of the hearth and home, Percy procures a blessing from his mother, which will allow him to descend into the Underworld for the second time. Here, Nico betrays Percy for information on his past, but then helps Percy to escape from confinement. The two boys then follow through with the original plan, which was for Percy to bathe in the River Styx and gain Achilles' power. Percy emerges from the Underworld in New York City, leaving Nico behind. Percy calls Annabeth and tells her it's time for the battle to begin. The campers, alongside Chiron, arrive and Percy organizes them (minus the Ares cabin, who refused to fight), and prepares them for an urban battle. They enter Olympus through the Empire State Building to prepare and meet Hermes, who is furious with Annabeth. He believes that she could have stopped the war by helping Luke before he was possessed, saying he would have listened to her. Before the battle begins, New York City is silenced by way of a powerful sleeping spell from Morpheus, the god of dreams, that puts all mortals to sleep. Despite being joined by the Hunters of Artemis; satyrs; naiads; dryads and other tree nymphs; Chiron's centaur cousins the Party Ponies, automatons fashioned by the late Daedalus; and the hellhound Mrs. O'Leary; Percy's forces are consistently forced back by sheer numbers. Kronos is not without losses, as Percy buffets the Titan Lord's brother, Hyperion, into submission, from where Grover's nature powers encase the Titan of the East in a massive maple tree. Annabeth is badly injured when she saves Percy from a blade thrown by Ethan, son of Nemesis, that would have hit Percy in his Achilles point and would have most likely been a fatal injury. Percy tells Annabeth this, informing her that his weak spot is the small of his back. Upon falling asleep, Percy has dreams of Kronos questioning Ethan about where Percy's Achilles spot was, but Ethan doesn't know. Rachel, a mortal who can see through the Mist, flies from a family island vacation to New York to tell Percy that he is not the hero of the Great Prophecy, and that it will influence his choice when he turns 16. More than that, she doesn't know who the hero mentioned in the Great Prophecy is. She also informs Percy that the Titans have a monster on their side that only a child of Ares could destroy, but the Ares cabin remains at camp. The monster arrives, and the campers learn that it is a drakon, a monster similar to, but more destructive than, a dragon. Right when all hope seems lost, an unknown camper posing as Clarisse tries to slaughter it but is badly wounded. The real Clarisse arrives on a flying chariot and kills the drakon by herself. The campers find out that the first "Clarisse" was Silena. She admits that she pretended to be Clarisse because that was the only way she could convince the rest of the Ares cabin to come and fight. With her last few breaths, Silena confesses she was the spy all along. She dies a hero, and not a traitor. Driven back to the blocks surrounding the Empire State building, Percy and his friends fight in a last stand to protect Mount Olympus from the massive army Kronos has amassed. Even when Hades arrives with his army, Kronos still manages to break through and enter Olympus. Percy and Kronos, in Luke's body, battle in the throne room of Olympus, without either side gaining a significant advantage. Ethan rebels against Kronos at the last minute, trying to kill him, but his sword ricochets back into his stomach. With his dying breath, he tells Percy that minor gods deserve better before falling into a fissure created by Kronos. Luke is shocked back into his non-evil self when Annabeth helps him remember his promise of family to her when he brutally smashes her across the throne room. The Great Prophecy hinges on Percy's decision to give Luke Annabeth's dagger rather than attempt to kill Luke himself. Luke injures himself at his mortal point (under his left armpit) and uses all his power in one strike on Kronos. With his dying breaths, Luke tells Percy that the minor gods should also have cabins at Camp Half-Blood. Annabeth tells Luke that she loved him as a brother, but Percy was the one she had always and truly loved. Luke sacrifices himself for Olympus and becomes the hero of the prophecy. Percy becomes the half-blood of the prophecy that would "reach sixteen against all odds," ending the war on the dawn of his 16th birthday. With Poseidon ambushing Typhon at the Hudson River, the Olympians manage to defeat him. Returning to the throne room, they grant Percy, Grover, Annabeth, Thalia, and Tyson rewards at the conclusion of their various quests. Percy, refusing godhood for himself, forces the gods to swear on the River Styx that they will recognize all of their children by the time they turn thirteen, Luke's dying wish. At camp, new cabins are built for every god, including Hades and all the minor gods. Rachel Elizabeth Dare becomes the new Oracle and speaks the next Great Prophecy- Seven half-bloods shall answer the call. To storm or fire, the world must fall. An oath to keep with the final breath, and foes bear arms to the Doors of Death Athena promises Annabeth that she will be the architect that redesigns a decimated Mount Olympus. Grover becomes a Lord of the Wild and a member of the Council of the Cloven Elders. Tyson is rewarded as well, by becoming general of the Cyclopes&#39; army and being given a &#34;stick&#34; (i.e. a new club). Percy is given the choice to become immortal, and a god, but he refuses. Afterward, Annabeth wishes Percy happy birthday and then kisses him. Percy gets the feeling that &#34;my brain was melting through my body&#34;. The other campers spy on them and dumps them in the canoe lake. Percy and Annabeth kiss underwater, and from there, start a relationship. Soon after, they immediately start work on the new cabins, rejecting the &#34;horseshoe&#34; style arrangement of the twelve Olympian god&#39;s cabins and instead adding more and more. Chiron praises Percy towards the end of camp, and Annabeth and the other campers cheer him on. Percy silently meets again with Hestia, and she gives him a smile and a wink, showing that she is proud of her young nephew. Percy and Annabeth run into the mortal world with Percy narrating, &#34;For once, I didn&#39;t look back.&#34;