John-117


 * "This child could be more useful to the UNSC than a fleet of destroyers, a thousand Lieutenants -- or even me. In the end, one child could be the difference between peace and a unwinnable war."
 * — Dr. Catherine Halsey referring to John-117.
 * — Dr. Catherine Halsey referring to John-117.

Master Chief Petty Officer John-117, also known simply by his rank as the "Master Chief" or (as is common in military culture) simply as the "Chief", is a Spartan-II supersoldier of the UNSC Navy's Special Weapons division. He served as one of the most important figures of the Human-Covenant War. After over thirty years of active duty, he is one of the most decorated war veterans of the United Nations Space Command.

The Battle of Trost
After an unknown amount of time, John, and the rest of Blue Team, arrive on Trost to assist in the capture of Rysa 'Vestam, where he is assisted by John-A222, Chad-119, and Marc Bedragare.