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Captain Vartan Gysirian was a human officer of the UNSC Marine Corps, serving with the UNSC Navy's Office of Naval Intelligence. In 2553, Gysirian was attached to ONI's 717th Xeno-Materials Exploitation Battalion.
An officer of the UNSC Marine Corps, Vartan Gysirian served with the UNSC Navy's Office of Naval Intelligence and was attached to the 717th Xeno-Materials Exploitation Battalion. During the battalion's operations to search for Forerunner ancilla Intrepid Eye on the human Outer Colony of Gao in 2553, Gysirian served as the aide-de-camp to Commander Murtag Nelson, the battalion's commander. Gysirian and Nelson were both stationed in the Montero Vitality Center.
On July 4, 2553, after the battalion's forces at the village of Wendosa came under attack by the Keepers of the One Freedom, Gysirian attempted to inform Nelson of the attack. However, Nelson was distracted with his discovery that Gao's Well of Echoes served as a cooling array for the planet's subterranean Forerunner structure. When Nelson decided he would recall the battalion's Spartan attachment, Gysirian was finally able to inform the commander of the attack on Wendosa. Nelson had a Pelican dropship and two UH-144 Falcons deployed from the Vitality Center to aid in the UNSC's defense, the Pelican and one of the Falcons were destroyed by forces of the Keepers while the second Falcon barely escaped. When a sniper moved to assassinate Nelson, Gysirian spotted the attacker and pushed Nelson to the ground, but Gysirian was killed by the bullet.
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