Constructed soon after the Human-Covenant War, the Imperative-class Arsenal Ship was conceived as a thought experiment for Project EXCALIBUR, intended to develop prototype technologies to field against the inexorable onslaught of the Covenant advance. After the conclusion of the war, approval was given from FLEETCOM to develop the Imperative-class further, and a number of technologies that were scheduled to enter service were incorporated into the design. During the War of Vengeance, the Imperative-class proved to be brutally effective. A rarity for a UNSC warship, the Invincible-class ships are designed to be completely unmanned, controlled by a single onboard Seventh-Generation "Smart" AI - most of its internal structure is dedicated to the AI data core and surrounding protection, as wel