|“||Blown to dust. Scattered to the wind. With luck, he's spread so thin that he'll never be able to form a consciousness again, much less a body. But don't mistake him for dead, Percy.||”|
Scattering is one of the few known ways to defeat an immortal.
As immortal beings, Protogenoi, Titans and Gods can't be killed. Even if they are cut up into many pieces, they can still survive and eventually rebuild themselves over time, especially if they possess a healthy host, as was shown with Kronos although this is different than scattering as only Kronos' physical form was destroyed.
The process of scattering is where the being in question receives a powerful blow that would destroy a mortal being utterly but where they can survive as an immortal. This destroys their physical form and scatters their essence to such an extent that it is believed that they won't ever be able to form a consciousness again, let alone a body. Thus they are scattered and harmless, though they aren't dead. If they are already weakened, the process is much easier, as was shown when Kronos was scattered by being removed out of Luke Castellan's body with a Celestial Bronze dagger. It was suggested in The Battle of the Labyrinth that Luke's body was holding Kronos' essence together after he was possessed, possibly explaining why this happened.
It appears that a scattered immortal's essence may be sent to Tartarus. Percy Jackson wondered if pieces of Kronos' essence were floating around and laughing at him as Percy and Annabeth Chase traveled through the realm. Koios also stated that Kronos' essence was so scattered that even the regenerative power of Tartarus couldn't heal his injuries.
During the Battle of Manhattan, Kronos battles the heroes before Annabeth Chase convinces Luke Castellan to retake control of his body from the Titan. Luke decides to sacrifice himself to stop Kronos as he is the only one who can strike his Achilles spot without Kronos regaining control. After Percy Jackson gives him Annabeth's Knife, Luke stabs himself in the side, near his armpit, where his Curse of Achilles was, mortally wounding himself and causing an explosion that is apparently the destruction of Kronos.
However, when Percy tries to comfort Hermes with his son's sacrifice to kill Kronos, Hermes tells him that Kronos is not dead as Titans can't be killed anymore than gods can and is instead scattered. Hermes explains it as "blown to dust. Scattered to the wind. With luck, he's spread so thin that he'll never be able to form a consciousness again, much less a body." However, Hermes warns Percy not to mistake that this means that Kronos is dead.
While talking with Bob, Koios tells him that Kronos was dissolved by "those impudent demigods" and that while bits and pieces of his essence remain, it's nothing that can ever be put back together again. Koios laments that there are some injuries that even Tartarus can't heal.
After taking inspiration from the defeat of Ouranos, Leo Valdez, Piper McLean and Jason Grace take on the task of defeating Gaea once and for all. Jason and the mechanical dragon Festus fly Gaea high in the air, cutting her off from the ground, her source of power and weakening her. Piper uses her charmspeak to put her to sleep and then Leo blasts Gaea with an intense supernova blast of fire which, combined with the power of an onager shot from Octavian, incinerates Gaea's physical form and scatters her essence (killing Leo and Octavian in the process). Like her son Kronos, Gaea is described as being scattered so thin that she won't be able to form a consciousness or a physical body ever again.
List of scattered immortals
It should be noted that there are a few other ways to permanently defeat an immortal. For instance it is shown that an immortal's essence can be absorbed by a more powerful immortal (an example being when Krios and Hyperion's esscences were sucked into Tartarus) or even a ghost using the correct spells.
A way to permanently destroy a god is called a shadow execration, a spell in which a god's sheut or shadow is captured and then destroyed. As the sheut is a vital part of the soul and stands for a being's impact upon the world, destroying it will kill the god beyond any sort of ability to return, something that even scattering can't do as the god is not truly dead with scattering.
- Both Hermes  and Nico di Angelo  are unsure whether the effects of scattering are permanent. However, in The House of Hades, Koios tells Bob that the Titans at least believe that Kronos can't be restored even with the healing power of Tartarus on monsters.
- The Trials of Apollo is the only series where the main antagonist is not scattered. This is because the Triumvirate are killed and Python is destroyed for good by being dropped into Chaos instead.