Blue Five

 was a UNSC Marine at the Second Battle of Harvest. He, along with a recon team, was scouting the area ahead of a UNSC army when the team was attacked, sending the Marines fleeing. It seems they were investigating the Relic. He radioed Blue Six, who was scheduled to join up with the recon team, and reported they were under attack. Blue Six's team was quickly wiped out and he too was wounded by a stray plasma bolt. Only seconds later, he was killed by an Elite. The Elite stared into the face of his lifeless prey and then tossed his body aside with an armada of Covenant behind him.