9th Shock Troops Battalion
From Halopedia, the Halo wiki
Elements of the battalion witnessed or participated in the Harvest Campaign, Battle for Arcadia, and Battle of the Etran Harborage in early 2531 before entering cryosleep following the loss of the Spirit of Fire's Slipspace drive.
They awoke twenty-eight years later at the Ark, and went on to participate in several operations against the Banished on the installation, including Operation: SPEARBREAKER and the defense of Fort Jordan.
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