The Three Fates take Luke’s shrouded body from the ruined throne room. When one Fate looks at Percy, Percy sees his own life rush forward to death, then understands that the blue thread he saw cut years earlier belonged to Luke, not him. Hermes stops the Fates long enough to bless and kiss his son goodbye, and Percy realizes the Great Prophecy’s lines refer to Luke’s sacrifice with Annabeth’s cursed knife.

Percy also understands that Luke survived the River Styx by holding on to his old promise to be a family with Annabeth and Thalia. Hurting Annabeth in battle awakened Luke’s mortal conscience, allowing Luke to defeat Kronos from within. Annabeth then collapses from her injuries, and Apollo heals her. Percy asks Zeus to raise a huge blue flag on the Empire State Building so Sally Jackson will know Percy survived and Olympus was saved.

As the gods repair Olympus, the surviving defenders arrive. Thalia is rescued by Cyclopes, Chiron is alive though injured, Rachel is reported missing after leaving the Empire State Building, and Nico enters with Hades to unexpected applause. Clarisse receives rare praise from Ares, while other gods acknowledge Percy and Annabeth in their own uneven ways. Grover mourns the fallen nature spirits, and Percy reassures him that the Wild can recover. Tyson and Poseidon arrive with the Cyclopes after chaining Typhon, and Poseidon embraces Percy with pride.

The Olympian Council convenes, and Zeus grudgingly thanks Hades and Poseidon for their decisive help. The gods reward the heroes: Thalia receives support for rebuilding the Hunters, Tyson is named a general of the Cyclopes, Grover is appointed to the Council of Cloven Elders, and Annabeth is made official architect of Olympus so she can redesign the damaged city.

Poseidon then calls Percy forward, and Zeus offers Percy the rare gift of immortality and godhood. Percy considers escaping aging and death, but thoughts of Annabeth and the dead demigods lead Percy to refuse. Instead, Percy makes the gods swear on the River Styx to grant his request, then demands reforms: all demigod children must be claimed by age thirteen, minor gods and their children must be recognized, Hades’s children must have a cabin, peaceful Titan-kind such as Calypso should be pardoned, and the pact of the Big Three must end. Athena supports Percy’s argument, the gods agree, and the Cyclopes form an honor guard as Tyson hails Percy as Hero of Olympus and his big brother.