O'Brien Biographical information Date of death September 2552 Physical description Rank Private Gender Male Weapons MA5B ICWS Assault Rifle Equipment Vacuum-sealed suit Chronological and political information Era(s) Human-Covenant war Affiliation UNSC Marine Corps
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Private O'Brien was a UNSC Marine aboard Reach Station Gamma, Dock 9, during the Fall of Reach.

Contents 1 Biography 1.1 Battle of Reach 1.2 Battle of Installation 04 2 List of appearances

BiographyEdit

Battle of ReachEdit

Main article: Battle of Reach

O'Brien, along with Staff Sergeant Avery Johnson, PFC Wallace A. Jenkins, and Private Bisenti, were fighting a group of Kig-yar when MCPO John-117 and PO2 Linda-058 boarded the station to destroy the navigational database of the ONI ship, UNSC Circumference.

Battle of Installation 04Edit

Main article: Battle of Installation 04

"Glad you could make it, Chief... we saved some party favors just for you."

— O'Brien greets John-117 on board the Pillar of Autumn

He was picked up with Johnson and the Chief when they took a pelican and flew back to the Pillar of Autumn. When the Pillar of Autumn was boarded, John-117 recognized him (but could not remember his name) and saved him from a Kig-yar soldier. He was killed either when the Covenant boarded the Pillar of Autumn or during the Battle of Installation 04.

List of appearancesEdit

• Halo: Combat Evolved (First appearance)
• Halo: The Fall of Reach
• Halo: The Flood