Blue Leader

"Blue Leader" was the designation of a Marine serving during the Battle of Earth. The Pelican Dropship he was carried on picked up Ruwan Ackerson, whose driving of a transport hog made them pick him up. Ruwan told him of the Key of Osanalan, and what it was - an imaginary object invented by him and his brother when children. Blue Leader judged that if the Covenant were readying their full-scale invasion of Earth, then Mars - where Ruwan's brother "James Ackerson" was stationed - had fallen to the enemy.