From Halopedia, the Halo wiki
Iratus was created by the Lux Voluspa company as part of an effort to research artificial intelligence creation utilizing brain donors from species aside from humanity. This included Jiralhanae donors; a decision considered by researchers "LV038" and "LV106" as something that was "always going to draw some attention eventually." The Lux Voluspa facility was ultimately breached by a cyberwarfare attack, with an intrusion package deployed using internally-sourced encryption and displaying a Jiralhanae retrieval signature. The originators of this attack were later indicated to be the Banished, who were able to steal the Iratus AI matrix from the facility.
After Cortana's defeat at Zeta Halo, the Iratus AI was present inside the Banished shipbreaking facilities on Camber. When Spartan-IVs Sigrid Eklund and Hieu Dinh were deployed to the facility, they were able to trap Iratus inside of Dinh's neural interface, compromising his armor and cognitive functions. Eklund was ultimately able to commandeer a Banished Phantom back to the Avery J. Johnson Academy of Military Science to seek aid from friendly forces.
List of appearances