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By 2552, Lieutenant Hall was assigned to the UNSC Iroquois under Commander Jacob Keyes. She proved to be a competent operations officer and saw action at the Battle of Sigma Octanus IV. Her performance and morale improved after the victory and she transferred to the recently promoted Captain Keyes' new ship, the UNSC Pillar of Autumn. She subsequently participated in the Fall of Reach and later the Battle of Installation 04.
She was most likely killed when the Covenant boarded the Pillar of Autumn.
Hall was known for maintaining a tidy and prim appearance. An ambitious officer, she constantly smiled to Keyes and tried to impress him, occasionally outperforming colleagues to do so. However, Keyes disapproved of her behavior. Over time, her attitude evolved and her relationship with Keyes improved. He came to respect her as a valuable part of his bridge crew.
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