Master Chief

Master Chief Petty Officer John-117 is a SPARTAN-II commando of the UNSC Naval Special Warfare Command. Taken from Eridanus II at age six, he is trained as a Spartan and later undergoes extensive mechanical and biological augmentation, giving him exceptionally strong bones, enhanced muscles and vision, and dramatically faster reflexes. After nearly 30 years of active duty, he is described as one of the UNSC's most decorated soldiers.