Eater

Eater (イーター) is the name of a type of lifeform in Digimon Story: Cyber Sleuth and one set of antagonists.

Design
All Eaters have elements of. They were designed by Oh!Great.

Digimon Story: Cyber Sleuth
Eaters are dangerous creatures who inhabit the reaches of Cyberspace EDEN. One ambushes Aiba, Nokia Shiramine, Arata Sanada, and their partners while in Kowloon Lv. 1. Aiba and Nokia hold it off while Arata activates an old terminal, through which they escape. Aiba, however, is unable to make it in time and ends up captured. By some miracle, they are able to log out but as a half-digital entity, giving them potent hacking abilities as well as the power to Connect Jump into digital spaces.

Eaters continue to be a recurring threat, as they feast on human data while in Cyberspace EDEN. They are behind EDEN Syndrome, as their consumption of human mental data leaves the original bodies comatose. They can also be found at the cores of Digital Shifts, where digital space bleeds into the Real World. Defeating them ceases the Digital Shift as well. Arata ends up investigating the Eaters with Aiba's help, eventually coming across the researcher Akemi Suedou.

Eaters turn out to not only have infested the Real World. They attacked the Digital World as well, turning it into a hellish landscape on the brink of destruction and prompting the to invade the human world. reveals that Eaters only are as they are because of the influence of humanity. The Royal Knights become divided on how to handle the Eater threat; one faction seeks to exterminate humanity while the other wishes for co-existence and unity. In the course of exterminating humanity, Crusadermon causes a giant Digital Shift that encompasses all of Tokyo, unleashing Eaters into the human world as well.

During the course of Aiba's battle to stop the Royal Knights, a hidden truth is revealed. When the first EDEN beta test occurred, Aiba, Nokia, Arata, Yuuko Kamishiro, and Yuugo Kamishiro managed to find a way into the Digital World. There, they encountered an Eater, who absorbed Yuugo and causing him to be the first sufferer of EDEN Syndrome. Eaters exist as a unified network that is constantly in communication with each other. Yuugo became part of that gestalt, slowing the Eaters' corruption of the world while at the same time causing them to seek out data to consume.

Eventually, the extermination faction of the Royal Knights is defeated. Suedou comes up with a plan to send the Eaters back to the Digital World to save humanity. He also reveals that the Eaters have a main unit titled the Mother Eater, which, if eliminated, would also stop the other Eaters. Yuugo is integrated with this core, so Aiba and their friends resolve to enter the Digital World, where the Mother Eater has merged with 's core, and end the threat once and for all. Fighting their way through King Drasil's defensive programs, Aiba manages to rescue Yuugo. Unfortunately, removing him from the Mother Eater means that the Eaters' erosion of the worlds will only accelerate. Suedou steps in at this moment, definitively showing that he has been working toward his own goals the entire time. He wishes to become one with the Mother Eater and King Drasil, merging everything together to create a new world without sorrow. Aiba must then take down the Mother Eater after Suedou merges with it and, despite the erosion they personally suffered through contact with Eaters, attempts to save Suedou as well. Seeing Aiba's actions and emotions, Suedou has an epiphany and decides to see what future Aiba will create.

Suedou reveals the Eater's true nature to Aiba. Eaters exist in a higher dimensional space that links worlds together. Their job is to observe and send data back to the higher dimension. When they came into contact with Cyberspace EDEN, they took on form and substance that corrupted them from their original goal. Suedou uses King Drasil's power to reformat the Eaters back to their original harmless form. These forms are like spheres of light, and speculates that phenomena such as  and s were actually Eaters who became visible due to Digital Waves. Nevertheless, Eaters are now harmless, and the possibility of them once again being corrupted is remote enough to be essentially impossible.