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Mission aboard Mona Lisa
During the Red Horse's classified mission in the Soell system, Sydney was assigned to Sergeant Zhao Heng Lopez's Marine detachment during a mission to investigate the prisoner transport Mona Lisa in Installation 04's debris field. Unbeknownst to the Marines, the mission had been commissioned by the Office of Naval Intelligence which had been conducting research on the Flood aboard the Mona Lisa.
After boarding the Mona Lisa through a cargo bay, the Marines were suddenly engaged by several unarmored Sangheili. After a brief firefight, Sergeant Lopez ordered Sydney, along with Cranker, Maller and Simmons, to guard their Pelican dropship in the bay and clean up the bodies on the floor while the others went to find Rabbit. Soon after, they were attacked by Pod infectors. Sydney and the other three Marines would then disappear, only to later return as Flood combat forms. Minutes before the Mona Lisa's destruction, the combat form that used to be Sydney attacked Corpsman Ngoc Benti, throwing her against a wall. The Flood form was quickly shot by Clarence, but not before managing to infect Benti.
Along with a number of other Marines, Sydney is not present in the motion comic adaptation of The Mona Lisa.
List of appearances