The creator of the Mind Trance system that allows for the use of I-Machines.
It is later revealed that Addams Forte Chevalier took on Kain Arisugawa's identity several years ago and that Ido is the true Kain Arisugawa. Kain was an arrogant and egotistical man obsessed with gathering data, willing to intentionally sacrifice 90% of humanity for the sake of researching and controlling Orichalt and the wandering planets known as Rajeev, which are ancient alien constructs that hunt down Orichalt. He secretly uses Alice, the terminally ill daughter of colleague Jennifer Record, as a test subject in order to create an "Orillian" as part of this plan.

Kain's utter lack of regard for human life and the revelation that Alice's fate was intentional causes his longtime friend Addams to snap and force him into an intentionally flawed Mind Trance, stripping his memories and imprisoning him in an immobile I-Machine body. However, Kain had a contingency plan in place to deliver a specially designed I-Machine that completely lacked identification data specifically to recover his consciousness with the designation "ID-0." As Ido many years later, he encounters Addams again, who returns his memories, though Ido rejects his past life as Kain Arisugawa. Through Kain's memories, Ido realizes that the Rajeevs adapt and evolve, making it impossible to permanently defeat them.
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