Master Sergeant Cortez was a Staff Non-commissioned Officer of the UNSC Marine Corps and an Orbital Drop Shock Trooper. Cortez was a member of the 105th ODST Division's contingent aboard the UNSC Kronstadt, and was in command of a fire team.
Some time between 2542 and 2552, MSgt Cortez and his fire team were tasked on a high priority mission on a Covenant-controlled planet known as Heian to assassinate a Prophet to interrupt Covenant supply lines. This mission was unusual in that a Spartan-II was given command over the mission. His team was deployed via SOEIV during a meteor storm to mask their approach. The mission almost immediately turned sour, when a fellow marine was killed during atmospheric entry. He nearly lost a second soldier, the team's secondary sniper O'Brien, whose pod begun to sink in the thick mud of a swamp he landed in. Cortez was about to begin to assist him when the Spartan took matters into her own hands and freed the entire Pod from the mud with pure brute strength. The team then began it's day march to their intended destination. During their trip they neutralized several Covenant Grunts and one Brute Chieftain.
Upon reaching their destination, Cortez and his fellow ODSTs set up a loose guard around the Spartan as she adjusted her Sniper Rifle for the assassination attempt, but was caught unawares by the sudden approach of the Brute they had earlier battled with who had not only survived the encounter but tracked the squad down to their location. The Brute, wielding a Gravity Hammer, attempted to smash O'Brien, but the Spartan managed to push him out of the way and take the brunt of the blow herself. After he and his fellow marines knocked down and killed the Brute, O'Brien finished the mission himself. With her dying breaths, the Spartan, Cal-141, handed Cortez the data she had gathered from the strange ruins scattered about the planet and asked him to bring them to Dr. Halsey. It is unknown whether he fulfilled this request.
Relationship with SpartansEdit
ODSTs are often known for their antagonistic feelings toward Spartan-IIs, and at the beginning of the mission Cortez and his team were all asked to put these feelings aside while working with a Spartan on a mission. After seeing Cal sacrifice herself to save one of his squad mates, it is likely Cortez has reconsidered these feelings. After the assassination, he is seen physically and verbally assaulting a fellow Marine who called into question the abilities of Cal.
- Cortez's name may be a reference to Timesplitters' Sergeant Cortez.