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 * September 25: A musical event, Believe, takes place at the UNSC Symphony Hall at 1900 hours, and performed by the UNSC's own Symphony Orchestra. It is centered on remembering Master Chief Petty Officer John-117 and his service to the UNSC.
 * After November 7: Onboard the , Cortana, showing clear signs of Rampancy, files a report on the history of the Forerunners and Humanity.