Here's a breakdown of the key events:
* The Battle of Manhattan: The Olympians, demigods, and even some monsters clash in a monumental battle against Kronos' forces in the streets of New York City.
* Percy's Heroic Actions: Percy faces off against Kronos himself, eventually managing to seal the Titan's soul in his own sword, Riptide. This act seals Kronos' fate and saves Olympus.
* The Gods' Decision: After the battle, the gods face a critical choice: remain in Olympus or return to Earth to rule over the demigods. Ultimately, they choose the latter, promising to create a new world where demigods and mortals can live in peace.
* The New Order: Percy is offered the position of Camp Half-Blood's head counselor, but he chooses to remain a camper. The demigods establish a new council with representatives from each Olympian god, working together to govern the new world.
* A New Beginning: The story ends with Percy and Annabeth sharing a kiss, setting the stage for their future together. The story concludes with a sense of hope and optimism, as the world moves towards a new era of peace and understanding between demigods and mortals.
While the series concludes, it's important to note that *The Last Olympian* serves as a springboard to the popular *Heroes of Olympus* series, where Percy and his friends face a new set of challenges.