Atriox began his career as a member of the Covenant, but soon grew tired of being sent in on suicide missions and rebelled against his Covenant commanders. Atriox quickly grew a loyal following of Jiralhanae, and formed the Banished near the end of the Human-Covenant War. After the war, the Banished grew in strength, using the loss of the Covenant to their advantage, absorbing former members of the Covenant, Covenant weapons, and the CAS-class assault carrier the Enduring Conviction. At the end of 2558, and after the Rise of the Created, Atriox led the Banished to Installation 00, where they pillaged anything and everything they could, before finally coming into contact with the UNSC Spirit of Fire in 2559. Atriox and the Banished survived the battle with the UNSC on the Ark, though the Enduring Conviction was destroyed by Installation 00's defense systems.