Siege of Paris IV
According to his CSV, Staff Sergeant Avery Johnson captured a crate of Covenant plasma grenades during the battle, from which he absorbed a 1,200-rad cumulative dose of radiation. This exposure caused Johnson to contract Boren's Syndrome. The staff sergeant later received a commendation for bravery during the battle.
In reality, Johnson did not actually contract Boren's Syndrome during the battle. The Office of Naval Intelligence fabricated the radiation story as part of a cover-up (known as the "Paris/BS Spoof") in order to hide Johnson's involvement in the top-secret ORION Project. Dr. Catherine Halsey would later mistake the falsified report of Johnson's service on Paris IV as factual, reasoning that he had acquired an immunity to the Flood due to his Boren's Syndrome.
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