From Halopedia, the Halo wiki
Mahmoud was a member of the UNSC Marine Corps. In October 2552, he was assigned to the prowler UNSC Red Horse under command of Sergeant Zhao Heng Lopez, who considered him to be one of her most competent subordinates along with his squad mates Benti, Clarence and Orlav.
Mission aboard Mona Lisa
Mahmoud was part of Sergeant Lopez's squad on a mission to investigate the prison ship Mona Lisa in the debris field of Installation 04 over the gas giant Threshold in the Soell system. Upon arriving on the Mona Lisa, the Marines were immediately engaged by a disparate group of unarmored Sangheili in a cargo bay. During the skirmish, Mahmoud was paired with Rabbit, before she disappeared and was infected by the Flood. Shortly after finding Rabbit's remains, the Marines received orders to purge the Mona Lisa's NAV databases. They then split into two teams, with Mahmoud being assigned to the team led by Sergeant Lopez, along with MacCraw, Percy, Rakesh and Singh.
Near the ship's infirmary, they found a lone survivor, who identified himself as John Smith. Smith consistently urged that they leave the ship, while refusing to divulge the whole truth about himself or the Flood outbreak. Eventually, Lopez's patience with Smith's secrecy wore off; she hit him and ordered Mahmoud to search him thoroughly. In doing so, Mahmoud found his ID badge, revealing that Smith was in fact a UNSC Major and ONI operative.
When Lopez did not obey Smith's orders to leave the ship immediately, Smith betrayed the team, slitting Mahmoud's throat with a knife, taking his assault rifle, and escaped. Mahmoud bled out in Lopez's arms, his last words being what Lopez thought was "...and then comes ice cream", in reference to a recurring phrase among their squad.
List of appearances