Araqiel

Araquiel was a "smart" AI assigned to Colonel James Ackerson.

As his private A.I., Araqiel was tasked to spy on Dr. Catherine Halsey and her research. His appearance is that of an elongated skull with long, demon-like horns, fire-filled eyes and jagged teeth. His voice is a low bestial growl or rumble containing a trace of far-off thunder.

He was left at CASTLE Base in 2552 during the Battle of Reach. He threatened Dr. Halsey and Kalmiya, accusing them of treason, after he attempted to stop her from breaking protocol and natural law by going into Ackerson's private data files. He even went so far as to threaten to fill Halsey's office with fatal levels of Narcozine Gas or to pressurize her office and cause pulmonary edema (The flooding of the lungs via the inability of the heart to remove fluids, effectively causing the victim to drown). Dr. Halsey responded by activating the fail-safe in his Riemann Matrix, effectively destroying him by sending a concentrated laser beam to burn it out.

Trivia

 * His name and avatar was based on those of a fallen angel described in the Book of Enoch.