Araquiel was the personal watchdog AI of Colonel James Ackerson. It appeared when Catherine Elizabeth Halsey was searching through X-Ray classified material, at CASTLE Base while the Covenant was about to start drilling for the Menachite Forerunner Complex. It ordered Dr. Halsey to cease those activities immediately. When Dr. Halsey didn't obey that order, it threatened to pressurize her office and cause pulmonary edema, it also threatened to release Narcozine Gas. In response to this, Dr. Halsey activated a special fail safe. The fail safe generated a pulse beam of high-frequency UV light, which cleared the high thought functions of the AI. This caused Kalmiya to wonder if she was also equipped with such a fail safe.
- Halo: First Strike (First appearance)