John-117

"They let me pick. Did I ever tell you that? Choose whichever Spartan I wanted. You know me. I did my research. Watched as you became the soldier we needed you to be. Like the others, you were strong and swift and brave. A natural leader. But you had something they didn't. Something no one saw, but me. Can you guess...? Luck."

- Cortana

Master Chief Petty Officer John-117 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 nearly thirty years of active duty, he is one of the most decorated war veterans of the United Nations Space Command, having fought in more than two hundred ground engagements against the Covenant and Insurrection, earning every major service medal and combat award except the Prisoner of War Medallion, as well as several dozen civilian honors. By August of 2558, he had completed 209 military operations, including 139 full campaigns; more than any other UNSC personnel on record. His complete record is only viewable with explicit UNSC High Command authority.

For much of his career, John served as the leader of Spartan Blue Team. As the war neared its end, most of John's fellow SPARTAN-IIs were killed in action during the Fall of Reach. However, John and his AI companion Cortana fled Reach and their vessel fortuitously arrived at Halo Installation 04, a one hundred millennia-old superweapon created by the Forerunners to destroy their parasitic enemy, the Flood, by killing all life in the galaxy. After destroying the Halo, the surrounding Covenant fleet, and the Flood forces on the ring, John returned to Earth and resisted the Covenant's impromptu invasion. Pursuing the invaders' flagship, the Master Chief encountered Installation 05, where a civil war soon broke out within the Covenant. Weeks later, John followed the remaining Covenant forces to the Ark, the Halo Array's control center, which he disabled before the Halos could be fired.

John went missing after the war's final battle in December 2552, having stymied the threat of the Covenant, the Flood, and the Halos. In the interbellum, John was lauded as a hero, and though he was officially declared MIA like all Spartans, he was ostensibly believed by the UNSC to have perished. After his recovery in July 2557, he played a key role in the conflict between the UNSC and the Didact's Promethean forces and a new Covenant faction, beginning on the shield world Requiem. This culminated in an attack on Earth and the Didact's temporary defeat, as well as the apparent loss of Cortana. John subsequently reunited with Blue Team and with their help, vanquished the Didact a second time. John and his Spartan compatriots went on to participate in numerous new missions for over a year.

During one such mission, John had a vision of a seemingly alive Cortana. This prompted him to go in search of her against direct orders, with the rest of Blue Team choosing to remain by his side. In response, the UNSC declared Blue Team absent without leave and sent Spartan-IV Fireteam Osiris to recover them. On Genesis, John and Blue Team learned that Cortana had assumed the Mantle for herself and was planning on using the Guardians to enforce peace across the galaxy. John rejected Cortana's offer to join her, prompting her to imprison him and the rest of Blue Team in a Cryptum. However, the Spartan-IIs were freed by Fireteam Osiris, with both Spartan teams traveling to Sanghelios while Cortana unleashed the Guardians on the galaxy.

Among most humans John is known simply by his rank as the "Master Chief" or (erroneously) the "Chief". Within the military he is most commonly identified as "SPARTAN-117" or the phonetic callsign "Sierra 117". As with all Spartans, John was regarded by the Covenant as a "Demon". However, John specifically was known as "the Demon", an epithet he earned after the destruction of Installation 04, though allied Sangheili soon came to address him as "Spartan". The Didact and the Warden Eternal addressed John and his Spartan teammates as Warriors or Warrior-Servants.

Childhood
"Well, he was a little younger than me, but, let me tell you, that boy did not look like a kindergartner. He was a big kid. My friend, Katrina, and I used to meet him in this vacant lot in the neighborhood. The three of us would build these obstacle courses out of random junk and then race. Ya' know, just kid stuff. On warm nights, sometimes our parents would let us go out to the green space and lie in the grass. And we'd just lie there, stare up at the stars."

- Ellie Bloom recalls her childhood with John to journalist Benjamin Giraud in 2558. John was born on March 7, 2511 on the Outer Colony of Eridanus II. He was raised by his mother and father and by the age of six he attended school at Elysium City's Primary Education Facility 119. Decades after he last saw her, John could still remember his mother as being very kind and smelling of soap. She sometimes took him down to the beach where he would play in the sand. John's closest childhood friends were girls: Katrina, Parisa, and Ellie Bloom. John, Ellie, and Katrina would often compete against one another in obstacle courses they built out of random bits of junk in a vacant lot in their neighborhood. He and Ellie, who lived just a few houses down on the same street as his family, would be permitted by their parents to go out to a green space on warm nights to lie in the grass and stargaze. At school, John was known for being competitive and for being particularly good at winning games of king of the hill that took place on a grassy hill at the end of Primary Education Facility 119's playground. He considered chess to be boring and too easy. By the time Dr. Catherine Halsey met John, he reportedly was not allowed to play gravball anymore due to his always winning. On August 3, 2517, John and Parisa were playing with one another at Lake Gusev. Parisa walked too far out into the lake and might have drowned but John saved her life. Afterward, he promised to marry her and always keep her safe. Parisa's father took a photograph of the two friends as they laughed hysterically at John's father's antics. Parisa would keep the photo with her long after she thought John had died. Over the next two weeks following the incident at the lake, John went on to score forty-five victories in king of the hill at school, leaving his opponents with a dozen broken bones, be they arms, clavicles, or fingers, and himself with a chipped tooth.

Abduction and conscription
"As per Naval Code 45812, you are hereby conscripted into the UNSC Special Project codenamed SPARTAN-II. You have been called upon to serve. You will be trained... and you will become the best we can make of you. You will be the protectors of Earth and all her colonies. This will be hard to understand, but you cannot return to your parents. This place will become your home. Your fellow trainees will be your family now. The training will be difficult. There will be a great deal of hardship on the road ahead, but I know you will all make it. Rest now. We begin tomorrow."

- Catherine Halsey welcomes the abducted children to their new reality. On August 17, 2517, John became the first child that Dr. Catherine Elizabeth Halsey, civilian consultant and scientific advisor for the Office of Naval Intelligence, paid a visit to. John was one-hundred and seventeenth among one-hundred and fifty children of similar age that had been selected based on specific genetic markers for inclusion in Project: SPARTAN-II, which only had facilities and funding for half that number. Halsey and Lieutenant Junior Grade Jacob Keyes found John at around 1130 hours on the playground at school while posing as parents inspecting the school for their little girl. John was in the middle of an intense game of king of the hill with eleven other boys and was clearly the dominant contender. When a pair of boys teamed up to take him down, he resorted to kicking, punching, and biting to get free before tearing back up the slop, declaring excitedly that he was king. As soon as the children were unsupervised due to the only other adult present taking a hurt girl inside to the nurse's office, Halsey made her move. She half-jogged over to the hill at the edge of the playground, halting just four meters from the hill's base. The game stopped at her approach, and some of the others teased John, thinking he must be in trouble for his aggressiveness, even though he was sporting a bruised cheek and a cracked lip himself. Halsey singled him out and asked if they might speak, to which he grudgingly agreed, coming down the hill and walking a short distance away with her. When she asked his name, John introduced himself and offered a handshake. When she asked what he had been doing, he simply said "Winning." Seeing that the boy liked games, she suggested that he try one of hers: she produced a quarter, once used as currency in United States of America on Earth, and dared him to guess which side would land face-up when she tossed it into the air. If he guessed correctly, she told him, she would let him keep the coin. Halsey released the quarter, sending it spinning end over end, but as it fell to the ground John caught it in his upturned palm, confidently exclaiming that it had landed with the eagle facing upwards. To Halsey's great curiosity, he was correct in his declaration. Satisfied that he would make the cut, she bid him farewell and returned to Lieutenant Keyes. Without hesitation, John ran back to the boys on the hill, eager to show off his prize.

At some point during the weeks that followed, John was abducted by ONI and replaced with a flash clone of himself. ONI operatives initially stole John directly from his bed while he was sleeping one night and were set to swap him for the clone then and there, but John woke up and had to have his mouth covered. The clone, likewise, woke up and the agents evidently made the decision to postpone the kidnapping. John was taken successfully some time later after leaving school. An agent lured him with a quarter like the one Halsey had given him, and when his guard was down, threw him into the back of a van. Before the doors shut, John came face-to-face with his doomed-to-die clone. John was put into cryostasis and whisked through slipstream space to Reach, the nexus of the United Nations Space Command's armed forces. Once revived on September 23, 2517, he and seventy-four other children were led into an amphitheater through four sets of double doors, each accompanied by a naval drill instructor. There, at around 2300 hours, far below the ground within a FLEETCOM military complex, Halsey informed them that per Naval Code 45812, they were thereby conscripted into SPARTAN-II. She explained that they had been called upon to serve and that they would be the protectors of Earth and all its colonies. John wrinkled his forehead in confusion at this, but sat up straight and listened to the doctor's words with rapt attention. Halsey told them they could not return to their parents and that from this moment on, the complex on Reach would be their home and their fellow trainees would be their family. And through the training that lay ahead of them would be difficult, she expressed her full confidence in their ability to overcome it. With that said, she told them to rest and that they would begin the next day. Chief Petty Officer Franklin Mendez had the children escorted to their barracks, fed, and put to bed. As they were being led away from Halsey, John kept his gaze on her, stoic and unmoved by the drastic turn his life had just taken.

Training begins
"Remember this: you don’t win unless your team wins. One person winning at the expense of the group means that you lose."

- CPO Mendez explaining trainees the main idea of teamwork.

John and the rest of the children chosen for the SPARTAN-II program were brought to the Reach FLEETCOM Military Complex, their new home for the next several years. There, Dr. Halsey informed the children of their new purpose: they were destined to become protectors of Earth and all its colonies. The next morning John discovered his service tag, stitched into his training uniform, and his new name: John-117. John began adjusting to his new life, training with other Spartans under Chief Petty Officer Franklin Mendez.

In their first training exercise, John was grouped with fellow trainees Kelly-087 and Samuel-034 in a game of "Ring the Bell". John rushed ahead of his teammates and crossed the finish line first; however, he was befuddled to learn that his team had lost, as Kelly and Sam came last. This taught John the importance of teamwork and the next day, his team scored higher. John soon bonded with Kelly and Sam, who would become his first and closest friends among the trainees. For eight years John was schooled in history, military strategy and tactics, and weapons, and was given extreme physical training. During his training, John used to tease Serin-019 and her habit of eating leftovers from meals of the other candidates.

John quickly proved himself to be one of the program's top candidates. Both Dr. Halsey and Chief Mendez identified him as one of four emerging leaders within the Spartan-II group, along with Kurt-051, Jerome-092, and Fred-104. Halsey believed John held both the skills and natural ability to lead the entire Spartan-II group. Mendez disagreed with her assessment, instead believing Kurt would fulfill the role as team leader. John's leadership skills were correctly observed, as the results from their mission clearly solidified his role as the overall leader of the Spartan-IIs. He also became the established leader of Spartan Blue Team.

Taking the initiative
"No one’s being left behind. We’re going to figure a way to get all of us out."

- John motivating his comrades during the Spartans' training exercise in Reach's Highlands

When the Spartans were eight years old, they were sent on a training mission in which they were dropped over a forest located deep in one of Reach's Highland Mountains. They were expected to get safely to their extraction vehicle, an Albatross dropship. The trainees also had instructions to leave the last member arriving behind, or their punishment would be severe. After organizing themselves, the Spartans looked to him as their leader. It was a role he was surprised to be given, but eventually accepted. When the group came across the Albatross, it was guarded by un-uniformed UNSC Marines, leading John to assume they were a threat. He quickly devised a plan to eliminate the hostiles, capture the dropship, and ensure the safe extraction of every team member. He also decided to take responsibility as the last arriving trainee singled out for punishment. He quickly hijacked the dropship with the help of Déjà, and attacked the guards with stones, injuring them severely. Chief Mendez was not initially pleased, feeling John had violated the boundaries of the test. However, both Mendez and Halsey quickly recognized John's initiative, and promoted him to Squad Leader. After this, despite the other Spartans rising in rank and leading independent teams, John remained the de facto leader of the Spartans as a whole.

Physical augmentation
"John-117"

- Dr. Halsey

At the age of 14, John underwent the dangerous SPARTAN-II augmentation procedures. These procedures resulted in the death of thirty trainees, with twelve more physically disabled. John was one of thirty three Spartans who made it through the process unscathed, while the wounded were sent to the Office of Naval Intelligence. Even before his cybernetic and genetic augmentation, at 14 years of age, John had a physical body of an 18-year old Olympic athlete. Far beyond the physical alterations, the enhancements boosted the Spartans reflexes, strength, enhanced eyesight, and rendered their bones nearly unbreakable. Following their treatments, John and the other Spartans were transferred to the to recover in a microgravity environment. During his first visit to the Atlas' gym, John was confronted by four ODSTs, whose sergeant then ordered the five of them into the boxing ring. In the ensuing fight, John inadvertently killed two of the ODSTs, and left the others severely injured. According to Major Antonio Silva, this incident was orchestrated by the Office of Naval Intelligence in order to test the Spartans' augmentations. While John had tried to avoid the confrontation, he nonetheless felt guilt at being forced to kill other human beings, but felt by following the sergeant's orders, he did the right thing. Then-ODST Anthony Petrosky, who witnessed the fight, would later refer to his comrades as "lambs to the slaughter"; he described John's punches as rapid-fire explosions, and that the fight was over in less than five seconds.

Following their return to Reach for further training, John and the other Spartans were soon relocated from their barracks in the FLEETCOM military complex into the abandoned titanium mines nearby. Left in the caverns virtually without equipment and pitted against Marines wearing heavy Mark I powered armor, the Spartans continuously overcame the opposition Chief Mendez planned for them using impromptu equipment and tactics.

Infiltration on Eridanus Secundus
"I have good news for you. The word has come down. Command has decided to test your unique abilities."

- Dr. Halsey to the Spartans before their first combat mission

John's first mission, codenamed Operation: TALON, was to capture Insurrectionist leader Colonel Robert Watts within the asteroid belt of the Eridanus system, where his homeworld was located. According to the plan, Blue Team, consisting of John, Kelly, Fred, Linda and Sam, infiltrated the Insurrectionists' base by hiding aboard the freighter Laden. Upon arrival they slid out of Laden and tracked their target to the barracks using previously marked cargo. The Spartans proficiently eliminated the guards and made their way to Watts' apartment, though John was shot in the side, with one bullet penetrating his body suit, bouncing off a few ribs, and causing a tremendous amount of internal bleeding, remaining lodged in his abdomen during the ensuing firefight. Careful not to kill Watts, they drove him into a corner, choked him into unconsciousness, and forced him into a sealed cargo crate. To make an exit, Sam used C-12 explosives to blow the main hangar bay doors. As the hangar bay decompressed, the Spartans escaped the rebels' base in a Pelican dropship stolen from the UNSC. The official results of the mission listed eleven dead enemy soldiers and an unknown number of rebel civilians. John received a Purple Heart upon the completion of the mission.

Chi Ceti IV


"John-117"

- Spartans

Three months after Eridanus, John and his Spartans were briefed on the massacre that took place on Harvest shortly after first contact with the Covenant. A short time later, the, under the command of Captain Wallace, brought the Spartans and Dr. Halsey to the Damascus Testing Facility at Chi Ceti IV, where they received their first suits of Mjolnir powered armor. When a Covenant ship, the Unrelenting, attacked the Commonwealth, John and the Spartan-IIs took part in their first engagement with the Covenant. The Spartans used thruster packs to launch themselves from a Pelican dropship. Each Spartan carried an ANVIL-II warhead to be used against the Covenant ship. Only two other Spartans reached the ship with John: Sam and Kelly. They entered the vessel through a puncture in its hull, caused by a MAC round from the Commonwealth. They succeeded in completing the mission and destroyed the Covenant ship, but due to a breach in Sam's armor, he was unable to leave the Covenant ship. Volunteering to stay behind and ensure the destruction of the enemy vessel, Sam was killed in the ensuing explosion. John was deeply affected at the loss of one of his closest friends. The victory showed that the Covenant could be beaten, but only at a high cost.

Alpha Corvi II
"Whitaker"

- John On December 3, 2525, a substantial Covenant force emerged from slipspace near Alpha Corvi and proceeded to began an attack on the system's second planet. It was at this point that the four remaining Spartan-II warriors of Blue Team were briefed on the attack. They were en route to the system aboard the,. Lieutenant Commander Yao told John and the others that they would be dropping on the outskirts of Jamshid and engaging the Covenant from the rear. Their objective was to lessen the pressure on the main UNSC garrison within the city so that a proper counterattack could be prepared. It was also imperative, they were told, that they operate independently of Ground Command and refrain from having any contact with anyone from the Marine Corps whatsoever. Upon arrival at the planet, Blue Team was redirected to the mining settlement of Black Reef and ordered to neutralize the invaders there and discover why it was being targeted. During their insertion via a D77-TC Pelican, Nora, an A.I. on the Persian Gate, introduced the Spartans to various scouting and reconnaissance enhancements their armor was outfitted with for this mission, including prototype active camouflage technology.

Blue Team was set down in a ground vehicle on the beach and immediately began taking fire from United Rebel Front troops encamped a short distance away. Kelly-087 and Fred-104 recommended taking them out quickly so they could move on to deal with the Covenant, but John-117 opted for a different option. He activated his active camouflage and crept up on the small band, only revealing himself when he could reach out and touch their apparent leader. John identified his team as being responsible for capturing Colonel Robert Watts and argued there was no way they could hope to beat them. He told them what had happened to Harvest and through appealing to their immediate common enemy, was able to get the leader, Whitaker, to agree to work together for the time being. At John's insistence, he ordered his squad to circle around and rendezvous with the rest of their forces at the edge of a lagoon. From there, they would hit the Covenant from one side and drive them toward where Blue Team lay in wait. In order to keep an eye on their uneasy allies, John sent along a surveillance drone to keep a visual on them. The plan worked, and Blue Team unloaded on the Covenant with BR55 battle rifles when the distance between them closed. During the fighting, John's drone was destroyed by a shot from a Kig-Yar's Type-25 plasma pistol. The Sangheili and Kig-Yar that remained escaped into the mouth of a tunnel that led deep into the mines beneath the reef's bedrock. John was determined to pursue them, not least of which because he was curious about a strange device a Sangheili took in with him. Whitaker informed him that though the mine was an expansive mess of tunnels, it only had the one entry and exit, meaning the enemy was trapped within it. Yao soon let John know that a host of new dropships were inbound. Most of them were heading for Jamshid, but three Spirits would reach Black Reef in just three minutes. Whitaker volunteered to hold the mine entrance with his people so the Spartans could pursue the Covenant forces that had vanished within.

The passageway traversed by Blue Team took them more than thirty meters below sea level. When a light was sighted ahead Fred asked whether they ought to activate their camo, but John opted to wait until just before a group of Sangheili, Kig-Yar, and Unggoy encircled them from multiple side tunnels. Unfortunately, the Spartans were still possible to make out, so John decided to drop the camo as they engaged the enemy. After disposing of their ambushers, he led them through one of the passages they had come from until they came into a large chamber filled with enemy forces led by a Field Marshal. A skirmish erupted but was interrupted when the insurrectionists above triggered used satchel charges and an M41 SPNKR to collapse the entrance to the mine. the resulting blast triggered a flood of water to rush into the chamber where the Spartans were fighting. When John ordered the others to sound off after escaping the flooding, it became clear that Linda had been separated from the others and was not responding to hails. John determined that their primary concern was still the completion of their mission, but that finding her would come afterward if necessary.

Silent Storm
"What matters is that our soldiers were fighting alongside the insurrectionists. Why would we protect the enemy?"

- Chyler Silva reacts to viewing leaked footage from John's helmet. In very early 2526, John was assigned to lead the other Spartan-IIs on a desperate counterattack designed to rock the Covenant back on its heels and to buy humanity the time it needed to gather intelligence and prepare its defenses.

In the first few months of this year, at least John and Fred were at one point deployed to support UNSC Marine Corps forces in a mission to capture a leader of the Insurrection. John found and secured their target, but the man warned him that someone else was coming. The mission parameters suddenly changed dramatically when the arrival of the Covenant forced John and the others to briefly ally with the rebels against their common enemy. John ordered his squad to fall back as soon as it became clear a third faction was present.

Circinius IV
"Stay close to me. It's your best chance of survival."

- The Chief to cadets Orenski, Lasky, Silva, and Sullivan. The colony world Circinius IV came under attack by the Covenant on April 26, 2526. John, Kelly, and Fred were deployed to the surface to evacuate residents. John tracked a distress signal from what remained of Hastati Squad of the Corbulo Academy of Military Science and found them covering in a training room with a Sangheili zealot about to attack. John crept up behind the zealot and stabbed it in the back of its neck with a combat knife, instantly killing it. He turned to the four cadets--April Orenski, Thomas Lasky, Chyler Silva, and Michael Sullivan--and told them that they didn't have much time to get out. John radioed Kelly and informed her that he had secured four survivors and that she ought to inform command and bring her team north for Pelican extraction at Evac Alpha. As far as John was concerned, these four cadets were by then the only remaining survivors on the entire planet. He told them to armor up quickly, as they had only fifteen minutes to get to their evacuation point. Sullivan pointed out that the nearby lockers were inaccessible to them, so John simply tore the doors from their hinges. Once everyone was sufficiently armed and armored, the group proceeded cautiously down a darkened hall of the academy. John eventually signaled a stopping point, as he had heard what might be enemies ahead. He ordered the cadets to stay quiet and to remain in place while he left to deal with any nearby threats. When John did return, he asked who the best shot among them was. Silva and Orenski were both singled out, and once he confirmed Lasky could drive an M12 Warthog, each of those three was given a role. Their goal was General Daniel Black's LRV parked just outside the building. When asked who he was, he simply replied that they could call him "Master Chief".

John and the cadets exited into the black of night and it wasn't long before they came under fire. Kig-Yar with Type-51 carbines and Type-31 needle rifles were posted on the roof above them. Sullivan was hit once with a Subanese crystal but John stepped in to let his armor take the brunt of a second which would have found its mark also. John returned fire with his MA5D assault rifle and yelled for the others to get down behind cover. He then committed to intentionally drawing the enemy's fire so that they could make it to the Warthog. John's M6H magnum soon landed consecutive headshots on the Kig-Yar. With the immediate attackers dealt with for the moment, he jumped down from the higher position he had attained and ordered everyone into the hog. They took off with Lasky driving and John manning the mounted M41 Vulcan machine gun. The Warthog carried the five of them down a forest road away from Corbulo. With only a little more than four minutes until they needed to be at the Pelican, John steered Lasky to bear right for an access directly ahead and to pick up speed. A Type-1 plasma grenade was suddenly lobbed into the road in front of the vehicle. The Warthog powered through the resulting explosion but they started taking fire from Kig-Yar among the trees armed with Type-33 needlers. John opened fire with the Vulcan and advised controlled bursts on the part of Orenski and Silva while also pointing out targets for them. He contacted Kelly once again and told her to track his position to be ready for evacuation. Without warning, the Warthog slammed into one of the Kig-Yar and this, combined with the damage it had already suffered from being hit with exploding Subanese crystals, slowed it to a halt, now unable to restart. John jumped off the back and immediately went to address Sullivan's worsening wound with biofoam, telling Orenski to take over on the chaingun. The biofoam made it so Sully could walk, but it was then that Chyler revealed she had also been hit and now that the canister had been emptied, it was even more imperative that they get to the Pelican soon. John commanded the cadets to take themselves north as fast as they could until they ran into his team. He then took off and soon found himself facing down an imposing Mgalekgolo. John was able to defeat the Hunter but when he found the cadets again, they had stopped moving because Silva had died. He offered his condolences and asked for any ammunition they could provide, as he had spent all his bringing down the Mgalekgolo gestalt. None of the cadets had any rounds remaining either, but Lasky produced an M9 fragmentation grenade and offered it to the Chief. Before long, the another Mgalekgolo, the bonded gestalt of the one which had just perished, went from hunting them to shooting its assault cannon at them. The three cadets and John tore through the forest to get away but stopped once they jumped down from a ledge and took cover behind it. Kelly was, at this point, insisting that John leave them, but he refused to do so. He implored her to give them more time and then ordered the Hastati remnant to go on without him while he dealt with their pursuer. Lasky responded by declaring that he would be a decoy so that the Chief could sweep in from behind. Before he could quash the idea, Lasky took off running. John let him distract the Mgalekgolo for a moment before making his move. When he rushed the hulking giant, however, it smacked him with its pavise shield and sent him flying backwards. The next time he made an attempt at the colony he used the shield to his advantage, climbing up it and vaulting over the mass of worms. He landed on its back and without a second's thought plunged the grenade into an exposed mass of Lekgolo. He flipped backward off of it just as the grenade detonated and blew the gestalt to pieces. John paused just long enough to gather up a piece of its armor before rejoining his evacuees. As daylight dawned, he let Kelly know they appeared to be in the clear and that she could have their pilot bring the D79-TC Pelican down in the clearing they had made it to. Everyone boarded and they were soon away. John gave the armor fragment he had gathered to Lasky, addressing the cadet as "soldier" and commending him for his performance. The Pelican escorted the Spartans and Corbulo cadets safely away from the planet's surface as. The glassing of Circinius IV had already begun that day, but fighting between the UNSC and the Covenant continued on the planet well into mid-July.

Fighting two wars
"You 'Spartans' have put quite a dent in our efforts to liberate the frontier worlds. Station Jefferson in the Eridanus asteroid belt last year; our destroyer Origami; six months ago, our high-explosive manufacturing facility; followed by the incident in Micronesia, and our saboteur cell on Reach. I didn't believe it until I saw the video. All by the same four-man team. Some said 'Blue Team' was a myth."

- General Howard Graves recounts the exploits of Blue Team against the URF. Though the colony of Green Hills was one of the first to be glassed by the Covenant soon after Harvest, like Harvest, the UNSC did not immediately abandon it. In 2527 John found himself fighting alongside ODSTs on the ruined world.

At least around two years and ten months after the initial attack on Circinius IV, John returned to the planet as part of Operation: PHALANX. The operation's goals included both the evacuation of a civilian population that still remained on the surface and the observation of the enemy's invasion patterns.

In mid-2530, John and the three other members of Blue Team successfully assaulted the United Rebel Front's Station Jefferson in the Eridanus asteroid belt. They dealt another blow to the rebels at some point between then and the last few months of the year when they boarded the URF destroyer Origami and completed a mission which removed the ship from the Front's possession. This campaign against the Front then led to John, Kelly, Fred, and Linda carrying out a mission to halt the manufacturing of of highly-powerful explosives at one of its dedicated facilities in October or November of 2530. At two points between then and the advent of May in 2531, the four-Spartan team deployed against pockets of the URF that existed on two of the UEG's core worlds: Earth and Reach. On Earth, they were deployed to deal with a rebel element in Micronesia, and on Reach, they put an end to a saboteur cell.

In early 2531, John was present for the Liberation of Harvest. At one point during the fighting, he arrived too late at the scene of a battle and found a fellow Spartan-II, Daisy-023, had been killed. Her corpse was without a helmet, so John kneeled to close his fallen sister's eyes and clasp her hands over her chest. He also took note of a loop with a tiny teddy bear on it that she had dropped, which he reverently placed between her fingers.

At some point following Operation: PHALANX but preceding Operation: WARM BLANKET in 2544, John is known to have participated in operations SWITCHBACK and HORIZON. Details regarding the former are highly classified, but the latter involved the destruction of Covenant exploratory fleet elements near the colony of Cascade.

At some point during the course of the war, John, aided by Fred and the rest of Blue Team, boarded a Covenant vessel called Perpetual Devotion. Once aboard, the Spartans overloaded the ship's reactor and made it off just before it exploded. On one occasion a large city on a colony world was under attack from a, which had launched hordes of Type-26 Banshees and landed ground troops, both of which were killing civilians indiscriminately. John and six other Spartans jumped from two D79-TC Pelicans, using their armor's integrated thrusters to land in the city and immediately begin engaging the enemy with MA5D assault rifles. At another time, John found himself alone far outside a human city facing down a hulking Jiralhanae with a Type-2 gravity hammer. Surrounded by a crashed Pelican and the corpses of dead Sangheili, and himself having been rendered weaponless, John met the Brute head-on and kicked off its chest, sending it reeling backwards.

Camp New Hope
"As you surmised, this was all for your benefit. We scraped our fissile material together and made sure it was done so sloppily that even your Office of Naval Intelligence saw it happen. We anticipated the miraculous Blue Team would be sent. I am not disappointed that your leaders' minds are still so easily read."

- General Graves to John-117 By April of 2531, the NAVSPECWEP's Spartan-IIs, and Blue Team in particular, had but put a significant dent in the efforts of the United Rebel Front free the Outer Colonies from UNSC control. A URF cell in the 111 Tauri system reached out to the regional UNSC Central Command and claimed to be willing to give up three stolen FENRIS nuclear warheads in exchange for medication and treatment by UNSC doctors being provided to some of their people whom had supposedly contracted Boren's syndrome. Command responded by covertly deploying Blue Team to the planet Victoria on May 1 with orders to recover the stolen warheads and target any Front leaders present. John-117, Kelly-087, Fred-104, Linda-058, and Kurt-051 infiltrated from the and approached the rebel base, Camp New Hope, under the cover of darkness. Kurt's inclusion during the mission marked the first time an additional Spartan had been added to the team since Sam-034 had died, bringing the roster back up to five once more.

John led his team to the perimeter of the rebel base and in quick succession, they silently eliminated perimeter guards by approaching them stealthily. For his part, John wrenched a guard's neck upward until he heard the sound of a dislocation. Once he got confirmation from his team regarding the others, he signaled them to move forward. John, Kurt, and Kelly ran for the base's gatehouse three-hundred meters away while Linda started to pick rebels off with her sniper rifle. Kelly surprised those within by dropping flashbang grenades from a hatch in the roof right before John breached the door by tearing the door and its frame from its steel reinforcement to the wall. By the time John brought his weapon to bear on the enemies inside, Kurt had already killed three. John dispassionately executed seven remaining men struggling to orient themselves with head-shots. He delegated the task of dealing with New Hope's security system to Kurt and Kelly, who put cameras and detectors into loops so that they wouldn't be revealed further in. She stated that they would only have a fifteen minute window in which they wouldn't have to deal with drones or dogs, given the current rotation and refueling schedule. John ordered everyone to move out, even though Kurt hesitancy and doubt about their ability to not being spotted. The Spartans skirted around one warehouse, went underneath an officers' barracks, and finally arrived at a central warehouse which John was certain held what they were seeking, thanks to a radiation counter he had been outfitted with for this operation. He had Kurt go secure a modified Warthog that was parked nearby so that they would be ready for a quick exit while the rest of the team spread out around the building. He authorized Linda to begin sniping rebels in her sight and then charged inside, followed shortly thereafter by everyone else but Kurt. Three FENRIS warheads were prominently displayed on steel racks but before John could do anything about it, he and the others were caught off guard by the sudden effects of an old antigravity plate pointed at their position. The URF commandos who had sprung this trap intended to trick the Spartans' Mjolnir into thinking it was under ten times the force of Earth's gravity. In response, the armor automatically increased its internal pressure and momentarily rendered its wearers unconscious.

John awoke to find himself propped against a wall, still fully armored but now fitted with a neural-inhibitor collar and still suffering somewhat from the effects of rapid decompression. Rendered unable to move, he was approached by the URF's own General Howard Graves, who proceeded to gloat about how easily the UNSC had taken their bait. Before anything else could happen, however, an Asteroidea anti-personnel mine came flying through the doorway, triggered and thrown by Kurt. The deadly explosion that followed was joined by three others after Kurt drove the warthog into the warehouse and tossed three more mines at Blue Team's captors. He freed his teammates, and at John's command, hopped back behind the wheel of the warthog once more and drove them out, now with the warheads. URF hostiles in the surrounding area realized what was happening and before long, the hog was taking fire from armor-piercing rounds and being pursued by three MAKO-class attack drones. To avoid being hit with a drone-fired missile, John ordered the modified vehicle's back hatch opened so he and Linda could snipe their flying pursuers out of the sky. The D77-TC Pelican that had brought them down to Victoria saved the team from the one missile that had been managed to be fired. With no time to spare, the pilot had the bird latch onto their vehicle and lift it skyward, carrying them like that all the way into orbit where the Bunker Hill was waiting to slip out of the system as soon as they were aboard. Kurt revealed it had been the large amounts of AP rounds the rebels had which had made him uneasy while in the guard tower. John told him that from there on out if anything else ever gave him pause during an op, he should make sure to report it right away.

Jericho VII
"Kelly-087"

- John-117 By 2535, John had been attached to the destroyer, commanded by Captain de Blanc. He had already witnessed the glassing of a least one world while working with de Blanc when the ship was deployed to Jericho VII in the Lambda Serpentis system. Covenant forces began a ground invasion of the planet on February 9, 2535, and for three days the Spartan-IIs of Blue, Red, and Green teams battled against them. During the fighting, John-117 commanded Blue Team, outfitted with its own D77-TC Pelican and comprised of himself, Kelly-087, Fred-104, Linda-058, and one other Spartan (Blue-Five). In order to stop the ground advance, Blue Team was tasked on February 12 with drawing out the Covenant's rear guard so that Red Team could slip through its lines amidst the confusion and planet a HAVOK tactical nuclear weapon at the aliens' staging area so that when the next ship landed to unload more troops, it would trigger the bomb's detonation. In the morning, Blue Team buried a spiderweb pattern of Lotus anti-tank mines along a hill near a beach, where John and the others planned to lure Covenant troops.

At 0500 hours, John's motion sensors alerted him to the presence of more than one hundred enemies near the position where the mines had been buried. He immediately signaled all teams to halt their progression and assessed the threat by way of a HUD-linked fiber optic probe which he snaked up and over a a three meter ridge of rock. The visual showed a valley absoutely overrun with Unggoy--easily a thousand of them. This same group had been responsible very recently for the massacre of the 105th Drop Jet Platoon. He passed along what he was seeing to the rest of Blue Team and instructed Kelly to use a pair of M41 SPNKRs to eliminate four stationary plasma cannons before unloading into the rest of them. Fred-104 and Blue-Five were told to help him with "crowd control" and Linda was given the job of setting off the mines at the opportune time. As soon as Kelly leapt into action, John, Fred, and Blue-Five opened fire with MA5B assault rifles, shooting armor-piercing rounds at first and then shredder rounds subsequently. John took a barrage fire from a Type-33 needler, but the Subanese crystal projectiles only bounced off his armor before detonating. The Chief gave the command to fall back in five seconds once Linda informed him the Covenant would have air support in the area in just two minutes. The closest Unggoy of the charging crowd was only three meters from their position along the ridge when John tossed two fragmentation grenades and turned to run. It took he, Fred, and Blue-Five thirty-two seconds to sprint half a kilometer up a sandstop slope, beneath which lay the buried mines and that ended at a cliff overlooking an ocean beach. Once they were a safe distance from the planned explosions, John gave Linda permission to detonate the Lotus mines. He, Fred, and Blue-Five picked off those that still remained after the devastating blasts.

Suddenly, five Type-26 Banshees appeared over a ridge and raced toward their position at over one-hundred kilometers per hour. After giving all teams under his command permission to fire and surviving the first pass the craft made at them, John ordered Fred and Blue-Five to perform a Theta maneuver. The three Spartans regrouped afterwards at the cliff edge and rappelled down steel cables already waiting for them. Fred was told by John to cover him while he prepared to detonate another trap: ten hidden fougasses packed with napalm and ammunition casings that would serve as shrapnel. When the five Banshees were just fifty meters away, John jumped from the cliff face and pressed the button sent them crashing into the sea. All five Spartans rendezvoused on the beach and John learned from Red Team that their part of the operation had been successful. He had Kelly patch him into SATCOM so he could report the victory to Captain de Blanc, but the captain informed him that things were going poorly in orbit and that the Spartans were being pulled out. In fifteen minutes' time, Blue Team had made its way ten kilometers down the beach and dusted off in its waiting Pelican. After docking in the Resolute's port bay, John took an elevator to the bridge, using the time it took to get there to review Red Team's after-action report. Though they had stopped the Covenant on the ground, it made little difference to the planet's ultimate fate. With the battle orbit lost, nothing else could be done. At thirty-million kilometers out from Jericho VII, John requested permission to stay on the bridge so he could observe its final glassing. Captain de Blanc granted him his wish, and for the next hour he stood completely still as he stared at the view screens. The captain then gave the order to leave the system.

WARM BLANKET
"John-117"

- Lucius Jiron In 2544, the Inner Colony, Miridem, came under assault by the Covenant. The colony was declared lost after over two weeks of fighting. During civilian egress, an evacuation craft carrying Dr. Catherine Halsey was intercepted at the edge of the planetary system and disabled before it could slip away. The Covenant evidently realized the value of Halsey as a prisoner, for only she was spared and taken prisoner aboard the Third Fleet of Glorious Consequence's flagship, Resplendent Fervor. The day after losing Miridem, Vice Admiral Berlin M. Tursk sent a message from the to Lucius Jiron, captain of the prowler PRO-49776, in which he told the captain he would be receiving Spartans shortly and that he ought to prep his OF92 booster frames for a quick and dirty extraction of the doctor.

By the time Blue Team was aboard the prowler, now composed of John-117, Kelly-087, Fred-104, Arthur-079, and Solomon-069, the Third Fleet of Glorious Consequence was being prevented from initiating slipspace jumps by the powerful magnetic field of the star, Ascon. Captain Jiron briefed the team before their departure and let them know they would only have a ten minute window to locate the package and return it to the UNSC. The Spartans saluted when he was finished and proceeded to their booster frames. John stayed behind briefly to ask what would happen if they ran out of time, to which Jiron said they would have no choice but to do whatever they had to in order to annihilate the fleet before it got away with its valuable asset.

The five EVA frames came under fire from pulse laser turrets and plasma torpedos almost immediately after the fleet noticed them. John gave advance warning of the incoming projectiles and lasers and had his Spartans optimize their frames for mobility. They all managed to evade the initial salvoes and even use their MITV pods to do some damage to the hull weaponry of the s shooting at them. Solomon and Kelly broke off to investigate a seemingly positive reading Solomon was receiving from the first battlecruiser he landed a scanning device on. John was skeptical of their prospects of locating their target so easily, so he flew his OF92 into the cruiser's hangar just in time to warn Kelly he suspected it was a trap. The two of them made it out just as an antimatter charge was detonated, destroying the ship and killing Solomon as well. At this point, multiple similar readings were being recognized across many ships in the fleet. John concluded they were all decoys like the the last and that their best bet would be to aim for the flagship. When a formation of Type-31 Seraphs bore down on the four remaining Spartan-IIs, he said to ignore them and to stay on target toward the Resplendent Fervor.

John commanded they stick to a tight formation and begin charge their M92 gauss cannons to fire at a single point in the carrier's aft hangar bay. Unfortunately, Arthur was killed while trying to defend the others from the Seraphs and Kelly had to abandon her frame to join Fred on his. With only two left, John had them fire everything they had, both gauss cannons and MITV missiles, at the Fervor's aft hangar bay. The Spartans even ejected from their booster frames so they could be sent slamming into the bay doors as heavy projectiles. John and the others survived the resulting explosions and entered the hangar encased inside a Z-4190 bubble shield. With only three minutes left to complete Operation: WARM BLANKET, John ordered a full sprint into the ship's interior. Armed with an MA5C assault rifle and dual M7 SMGs, John took down Jiralhanae, Kig-Yar, and Unggoy as they raced down corridors in search of their target. Fred used an M6 Spartan Laser to create openings in the ship's bulkheads twice for them to pass through. Suddenly, the Sangheili Major, Thel 'Lodamee, and two minors ambushed John and the others. Fred leapt in to assist John, killing one of the minors, and elected to stay behind to face down the other two so John and Kelly could keep running ahead. At this point, the fleet's Supreme Commander, Luro 'Taralumee, initiated the splitting of the ship into detached sections in an effort to halt their advance. John and Kelly, in vacuum between the dispersed portions of the carrier, locked hands and she swung him toward the foremost section. He only hesitated briefly upon landing, regretting leaving his closest companion behind.

John chanced upon the doctor soon after he made his way forward. She was still in cryostasis within a cryotube taken from the evac craft she'd been kidnapped from. John initiated a quick thaw and woke her, jokingly asking if she slept well. Halsey thanked John, relieved to see him. The two made their way for utility shuttles they could use to escape but were met by Thel 'Lodamee, whom had evidently gotten away from Fred. John opened fire with his MA5, but the Elite's Type-1 energy sword was able to block the bullets. Surprisingly, Thel tossed John a second sword. Realizing he was being challenged to a duel, the Chief activated it and before long the two were clashing blades as Halsey looked on. At that moment the fleet became clear of Ascon's magnetic interference, however, and 'Tarulamee decided to once again break off the portion of the ship John, Halsey, and Thel were in before jumping to slipspace. Rather than leave the major behind, though, he was caught up in a gravity field and pulled back to the foremost section. Now free to leave, John and Halsey boarded a Ren and blasted away from the remainder of the ship before it was scuttled. They were accosted by a group of Seraphs left behind by the fleet, but were saved thanks to the combined efforts of PRO-49776 and another Seraph that had been commandeered by both Kelly and Fred.

Once safely back aboard the prowler, John mourned the losses of Arthur and Solomon and considered whether he could have beaten the major had their duel continued, as he had been exceptionally strong. John resolved to be stronger in the future, which Halsey agreed they would all need to be. Soon after the successful rescue of Doctor Halsey, John was ordered to redeploy to Miridem as part of Operation: IRON FIST, with the dual goals of denying the Covenant access to valuable assets on the planet and the partial recovery of critical cyberinfrastructure assets alike.

Invasion of Draco III
"Everyone else might have cheered at the images of humanity's superheroes diving in and kicking some Covenant ass, but all I could think about was how useless it was to pin our hopes on a few handfuls of super-soldiers who couldn't possibly be everywhere we needed them to be."

- Edward Buck recalls his reaction to watching footage of the Spartans taking back Draco III. On January 10, 2545, the Covenant began a brutal assault on the colony world of Draco III. Its defenses were overwhelmed in a short amount of time and the Covenant began to land forces on the surface. The majority of the Spartan-IIs, including John and Linda-058, were directed to reinforce the colonists. Before arriving, the Spartans were shown footage of a massacre on the surface which had been relayed to them via satellite linkup. John and the others could only watch as humans were herded together and then torn apart by ravenous Unggoy and Kig-Yar. By the time the Spartans finally made it to Draco III, there was nobody left to rescue. Despite being too late to save the victims, John and the others made sure that they were avenged. Their retaliation resulted in the deaths of every Covenant soldier on the planet and footage of it was broadcast to the public in order to boost morale.

Sigma Octanus IV


"We've come to take Sigma Octanus IV back from the Covenant, Corporal. To do that, we're going to kill every last one of them."

- John-117 to Corporal Harland upon the Spartans' arrival on the planet

By summer 2552, he had received every medal awarded by the UNSC except the Prisoner of War Medallion. During the Battle of Sigma Octanus IV in July 2552, John led a platoon of Spartans to aid the Marine forces on the planet. John, leading Blue Team, infiltrated the city of Côte d'Azur to detonate a HAVOK nuclear warhead to clear Covenant forces from the city as part of Operation: OCEAN BREAKER. However, the heavy Covenant presence outside the Côte d'Azur Museum of Natural History raised his suspicion, prompting him to lead Blue Team into the museum. Inside the museum, John found out that the Covenant were scanning a piece of rock while sending the information to a Covenant ship in orbit. After dispatching two Mgalekgolo guarding the rock, he took the rock and left the museum with his Spartans. John ordered the detonation of the HAVOK warhead in the city, and, along with other Spartans, Marines, and rescued civilians, returned to the, which ferried them to Reach.

Fall of Reach
"Kelly-087"

- John-117

On August 29, 2552, during the Covenant's ongoing invasion of Reach (knowledge of which had been kept from the Spartans), John received an upgrade to the Mark V Mjolnir armor as well as an upgrade to his neural interface, allowing him to support an artificial intelligence. He was then introduced to and partnered with the AI Cortana, who would become his closest friend and confidant. Before embarking on a high risk mission to capture a Covenant Prophet, the two were put through a suicidal test in an attempt by Colonel James Ackerson to defame the SPARTAN-II program. Despite the dangers, John refused to cheat the test and was determined to win it by Ackerson's rules. Despite nearly being killed, Cortana and John's teamwork allowed them to prevail in an impossible situation, the first of many such accomplishments.

On the following day, the majority of the Spartan-IIs were deployed to protect the generators which powered Reach's twenty orbital defense platforms. John, with Linda and James, was sent to Gamma Station to destroy an unsecured navigation database onboard the prowler. If the Covenant obtained the database, they would discover the location of every human world, including Earth. The NAV database was destroyed, but Linda and James were ambushed by Covenant Sangheili. John fought one such Sangheili in close quarters combat, killing the alien before he could compromise the mission. The rest of John's team was not so fortunate; James was lost in space and Linda was critically wounded during the fighting. John saved four Marines on the station, including Staff Sergeant Avery Johnson who, unknown to John, was in fact a Spartan-I from the ORION Project. The team returned to the and was placed into cryo-sleep as the ship landed on and later fled Reach, and, following the Cole Protocol, jumped into slipspace. With coordinates discovered by Cortana, and in the hopes of leading the Covenant away from Earth, John would soon find himself involved in the most critical battle of the war to date.

Installation 04


"Captain Keyes"

- John-117

Upon the ship's arrival at Halo Installation 04, it soon became clear that the Halcyon-class cruiser had been followed through slipspace by a dozen Covenant ships. These vessels engaged the Autumn and sent several capture parties to board the ship. Captain Jacob Keyes ordered John to be woken from cryosleep, and tasked him with ensuring the escape of Cortana while he crash-landed the Pillar of Autumn on the then-unidentified ringworld.

Believing himself to be the only surviving Spartan-II, John launched several successful guerrilla attacks against the Covenant. Initially, the fierce fighting on Halo was solely between UNSC and Covenant forces, but after the Covenant unwittingly released an ancient parasite, the Flood, the majority of both forces became infected or destroyed.

John was sent by the Installation's monitor, 343 Guilty Spark, to retrieve the Index, an activation device for the Halo ring. Seeing the danger posed by the Flood first hand, John willfully took up the role as a Reclaimer. Upon John's return to Halo's Control Room, Cortana revealed that Halo's true purpose was not only to destroy the Flood, but prevent its spread by targeting all sentient life within its blast radius. John was then forced to disrupt Halo's firing system by disabling the ring's phase pulse generators in order to delay the Monitor's plan.

John carved a path through the three-sided conflict among the Covenant, the Flood and the Forerunners' Sentinels. Soon after, he tried to rescue Captain Keyes, but was too late. Captain Keyes had been transformed into a proto-Gravemind Flood form. After infiltrating the Covenant cruiser Truth and Reconciliation, the Chief managed to retrieve the Captain's neural implants, which he used to activate the Pillar of Autumn's self-destruct sequence. After the sequence was aborted by 343 Guilty Spark, he proceeded to manually overload the fusion reactors, which would subsequently destroy both the Pillar of Autumn and Installation 04.

After successfully destroying the fusion reactors on the Pillar of Autumn, John used a Warthog to reach the extraction point where Pelican Echo 419 was to recover him. John reached the extraction point, only to witness the Pelican crashing after being shot down by a pair of Banshees. Quickly making his way to the ship's Launch Bay 7, John used the sole Longsword fighter stored there to escape Halo just before the Autumn ' s engines detonated, destroying the Halo.

Return to Reach


"He sent his team down to the surface of Reach... sent them to their deaths. What commander wouldn't go back? And what commander wouldn't hope that they were alive? No matter what the odds?"

- Lieutenant Haverson about John's motives

After the destruction of Alpha Halo, Cortana and John discovered three cryotubes floating nearby, one containing Linda-058, and retrieved them. Soon after, the Covenant flagship Ascendant Justice and several cruisers appeared from behind Threshold, having taken cover from Halo's destruction. A nearby Pelican dropship which had docked on an asteroid floating among Halo's debris field fired at the cruiser to distract it. After a successful escape from the Covenant battle group, John linked the two vessels and brought its passengers aboard the Longsword; these included Lieutenant Elias Haverson, Corporal Locklear, Warrant Officer Sheila Polaski and Staff Sergeant Avery Johnson. After a joyful reunion, the surviving humans aided John in capturing the Ascendant Justice. The survivors commandeered the ship and traveled to Reach to look for any Spartans who may have escaped the planet's glassing.

John succeeded in locating some of his fellow Spartans on Reach, along with Vice Admiral Danforth Whitcomb and Dr. Catherine Halsey. They returned to the super-carrier and linked it with the damaged UNSC frigate Gettysburg. Before traveling to Earth, they decided to head into the Eridanus system where they discovered that the rebel base, Eridanus Secundus, was still intact, now led by Governor Jacob Jiles. After receiving some repairs, they were forced to abandon the rebels in the face of a Covenant assault, and made their way toward the Covenant refit-and-repair station, Unyielding Hierophant, where an enormous fleet was poised to invade Earth.

Raid on Unyielding Hierophant
"We're going to take this fight to the Covenant. We're going to launch a first strike."

- John-117 to his team about mission ahead of them

John and remaining Spartan-IIs Linda-058, Grace-093, Will-043, and Fred-104, focused on finding a way to stop the Covenant from reaching Earth, the location of which had been compromised. They decided to destroy the Unyielding Hierophant in order to slow the fleet's departure. The Spartan-IIs infiltrated the station, which was located in the Tau Ceti system, and after spending eleven hours on board, they arrived at a temple where a copy of Cortana warned them of the nearby Jiralhanae guards. Linda took up a sniping position and the other four Spartans entered the temple. John was nearly killed by ambushing Brutes, but the team managed to slay their attackers quickly. Grace, however, was torn in half by three Brute Shot rounds. John activated the fail-safe on her armor, denying her body to the Covenant.

The team then sabotaged the generators in the Unyielding Hierophant, and as they escaped through a side door, the fail-safe on Grace's armor activated, disintegrating a pursuing Covenant lance. John, Fred, and Will were quickly spotted by Banshees, but their pilots were killed by Linda's precision sniper fire. The Banshees were then recovered by the Spartans. John doubled back to retrieve Linda and the team escaped by destroying a glass atrium, exfiltrating via space-walk and arrived back at the Gettysburg.

Vice Admiral Whitcomb and Lieutenant Haverson piloted the Ascendant Justice straight into the Unyielding Hierophant. Whitcomb discussed the battles of the Alamo and Thermopylae briefly with John, then prepared to fight the Covenant off while the Unyielding Hierophant's fusion reactor detonated. Each of the five hundred Covenant ships maneuvered next to the Ascendant Justice, desperately to recover a Forerunner navigation crystal. The Admiral and the Lieutenant were both killed when the station's fusion reactor exploded, annihilating 486 ships of the Covenant fleet, leaving only around a dozen intact. The paltry survivors of the Prophet of Truth's fleet would later be committed to reinforce the Prophet of Regret's botched attack against New Mombasa on Earth. John left after witnessing Whitcomb's and Haverson's sacrifice, and arrived at Earth with the last members of his team, Linda, Will, and Fred, as well as Johnson and Cortana. They also brought with them news of the Covenant's imminent invasion.

Before she left the group to embark on her own mission, Dr. Halsey presented John with a dilemma regarding the combat data on the Flood which she had analyzed. Providing the standard data set to Lieutenant Haverson would protect Sergeant Johnson from possible experimentation by ONI. However, providing him the complete data, which contained reference to Sergeant Johnson's escape from the Flood due to his Boren's Syndrome, would supposedly result in Johnson's death. While John initially gave the complete data to Haverson, after the lieutenant's self-sacrifice he decided to spare Johnson's life and destroyed the crystal containing the full data.

Battle of Earth


"Cortana"

- John-117

Aboard Cairo Station, John received a suit of Mark VI Mjolnir armor and attended an award ceremony with Lieutenant Commander Miranda Keyes (receiving a posthumous award for her father's service) and the newly promoted Sergeant Major Avery Johnson. The ceremony was interrupted by the arrival of the Covenant Fleet of Sacred Consecration, initiating the Battle of Earth. Upon discovering a Covenant antimatter charge on board Cairo Station, John fought his way through waves of Elites, Grunts, and Drones until he reached the bomb, allowing Cortana to access and deactivate it. Feeling he could put the device to better use than the Covenant, John launched himself and the charge towards a Covenant assault carrier. A timely bombing run by Longsword interceptors opened a breach in the warship's hull, allowing John to direct the bomb into the ship's fusion core. With seconds to spare, he launched himself back into space just before the vessel detonated. The quickly recovered the free-falling Spartan.

John was then deployed to New Mombasa, East African Protectorate aboard the In Amber Clad, in an attempt to board the Solemn Penance, the Prophet of Regret's flagship. Both of the strike teams' Pelican dropships were shot down by a Type-47A Scarab. John and the surviving Marines fought their way to the other Pelican's crash site. After rendezvousing with Gunnery Sergeant Stacker at Hotel Zanzibar in Old Mombasa, the Master Chief destroyed Covenant infantry and armor along the shore of the city as he chased the Scarab. Upon arriving at the edge of Old Mombasa John commandeered a Scorpion Tank from Sergeant Major Johnson, which he used to punch a hole through the city's alien occupiers.

After intense fighting through numerous highway tunnels and suburbs, John reached the industrial zone, where Marines under the command of Sergeant Banks were pinned down by Covenant forces. With the assistance of the Marines and a large stockpile of weapons, John boarded the massive Scarab and destroyed it from the inside. John was then transported to In Amber Clad to intercept the Prophet of Regret's flagship. When the flagship started to enter slipspace, Lieutenant Commander Keyes was granted permission to follow it. John, and all on board In Amber Clad, were transported to Installation 05.

Installation 05


"This is not your grave...But you are welcome in it."

- The Gravemind to John-117 after capturing the latter

Forced to act quickly at Installation 05, John was deployed groundside in an SOEIV along with several Orbital Drop Shock Troopers. Cortana told John of the Prophet of Regret's intent to fire Halo and complete their religion's Great Journey. Recognizing the extreme nature of the threat, John was tasked with locating and assassinating Regret. He tracked the Prophet to a vast temple in the middle of a lake, but not before witnessing hundreds of Covenant vessels coming out of Slipspace, followed by High Charity, the Covenant's holy city. Quickly disposing of a force of Sangheili Honor Guards, John assassinated the Prophet and escaped the temple before it was destroyed by a nearby carrier. John jumped off the edge of the structure and into the lake below.

Losing consciousness from the impact, John was captured by the Flood's central intelligence, the Gravemind. Shortly after, the Arbiter was also captured. The Gravemind appealed to John's common interest in preventing the firing of the Halo array. Reluctantly, John agreed. The Gravemind then tasked both captives with locating the Index, sending them to the two most likely locations where it could be found. John was sent to High Charity, interrupting a sermon by the Prophet of Truth. The conflict between the Sangheili and Jiralhanae came as a direct result of John's assassination of a High Prophet, leading the Covenant to civil war.

John wasted little time in devastating the ranks of the Prophet's guardians, chasing the surviving Hierarchs through High Charity. John nearly cornered the San'Shyuum and their Brute escorts, but was too late to prevent Truth's escape. A dying Prophet of Mercy, infected through the throat by a Pod infector, snarled that Truth had ordered his Dreadnought to Earth where he would complete the destruction of the human race. John then tore the Pod infector from Mercy and crushed it with his armored hand. While this act killed Mercy, he was shortly thereafter resurrected as a Flood-controlled puppet. John faced another crucial dilemma: the Covenant had the Index and could activate Halo; however, Earth's Home Fleet stood little chance of withstanding Truth's remaining forces.

Ultimately, John was forced to leave Cortana behind. In the event of Halo's activation, she would detonate In Amber Clad's reactors directly and perish with the city. John boarded the Forerunner Dreadnought, but not before promising to return for Cortana after he stopped the Covenant.

Hunt for Truth
"Lord Hood"

- John-117

Onboard the Forerunner Dreadnought, when it passed near Jupiter, John was contacted by Io Station, but maintained radio silence. Rampaging through the ship, he attempted to find the Prophet of Truth and assassinate him. John found himself faced by an extremely large force of Covenant troops, including at least three Hunter pairs, who fired on him simultaneously. He was hit by several assault cannon beams, and was confronted by a Brute Chieftain who began to interrogate him about the "Key of Osanalan". However, the Spartan stuck the Brute with a plasma grenade and escaped. The Chief continued his push through the ship, eventually arriving in Truth's chambers and setting his sights on the Prophet. With Truth in his sights, he was caught by surprise by a Jackal and shot in the back. He fell and landed right in front of the Prophet's Brute guards. While the Chief managed to get several shots at Truth, the Prophet was shielded by his gravity throne and made his escape, while the Chief was left to fight off dozens of Covenant. John, having failed in his attempt to take control of the Forerunner Dreadnought's trajectory, fought his way out of the Forerunner ship's airlock in a commandeered Ghost. On the surface of the Dreadnought, he was ordered to find a way to return to Earth quickly.

Return to Earth
"Crazy fool! Why do you always jump? One of these days, you're gonna land on somethin' as stubborn as you are! And I don't do bits and pieces!"

- Sergeant Johnson about John's escape methods

John exited the Dreadnought and crash-landed on Earth, where he was found by Sergeant Johnson, the Arbiter, and the rest of their Marine squad. Johnson believed the Chief to be dead, and requested heavy lifting gear in order to recover the Spartan's body. However, John awoke to battle-ready condition only moments later, showing his incredible tolerance to pain and shock. He attempted to attack the Arbiter, believing that the Elites were still a human enemy. Johnson informed him that the two races were now allies, as the disillusioned Arbiter and the Sangheili had been expelled from the Covenant.

John and the Marines traveled through the jungle, searching for evacuation to a nearby military base. Johnson and his team split up from John and the Arbiter. The sergeant and his squad were captured by Prophet-loyalist Covenant Brutes, although they were soon rescued by John and 'Vadam. After taking heavy fire from Phantoms, a Pelican dropship evacuated the team to a UNSC base known as Crow's Nest.

The hidden facility soon came under attack, but not before Fleet Admiral Terrence Hood told John his plan to counterattack the Covenant forces above and surrounding the excavated Forerunner artifact near Voi. Lieutenant Commander Keyes decided to evacuate all troops before Truth could launch his assault. John, Thel and the remaining UNSC Marines defended the base during its evacuation, planting a massive bomb to destroy the base along with the invading Covenant forces. The Master Chief fought his way through dozens of Jiralhanae warriors, escaping the explosion in an elevator. He met up with several Marine survivors underground, and they escaped the base and headed for the city of Voi along Tsavo Highway, crushing Covenant resistance on their way.

At the Battle of Voi, John dashed towards what was believed to be the Ark. Instead, the artifact opened a slipspace portal to the Ark. With Marine support, John and Thel 'Vadam destroyed three Anti-Air Wraiths, a Scarab, and a Covenant anti-aircraft battery, allowing Lord Hood's remaining frigates to fire upon Truth's Dreadnought. Unfortunately, MAC rounds had little effect on the Forerunner Dreadnought, and Truth fled through the Portal with his remaining loyalist forces. The UNSC remained behind on Earth to determine their next move.

Just as the battle seemed over, a Flood-infested Covenant warship crash-landed in Voi. John and his allies fought to contain the Flood infection, eventually destroying the infected warship. During the battle, Shipmaster Rtas 'Vadum came to aid the UNSC. He deployed a Special Operations Sangheili strike team through orbital insertion pods, assisting John as he attempted to recover a fragment of Cortana hidden aboard the vessel, who he learned was on the crashed vessel. Aided by the unexpected appearance of 343 Guilty Spark, John retrieved the damaged data device and was brought aboard 'Vadum's flagship, Shadow of Intent. The Sangheili were able to stop the Flood infestation by glassing the city and its surroundings, much to Hood's anger.

The Sangheili and the UNSC watched Cortana's recording, which contained a warning that High Charity, now overwhelmed and controlled by the Gravemind, was heading for Earth. However, she offered hope, hinting at a way to stop the Halos from firing and to neutralize the Flood. Convinced of the reliability of Cortana's message, John resolved to journey to the Ark, while Hood mobilized remaining UNSC forces on Earth. John accompanied a joint UNSC-Sangheili task force through the portal aboard the to the Ark.

Installation 00
"John-117"

- Cortana

Recognizing the fate of all life within the galaxy was at stake, the UNSC-Sangheili task force was determined to stop Truth from activating the remaining six Halos at any cost. The infantry strike team descended in Pelicans and Phantoms while the Shipmaster's fleet fought a 3:1 battle against an armada of Brute controlled ships. John landed on the surface of the Ark, eliminating Covenant loyalists in the area to secure a landing zone for UNSC frigate, and to find the Ark's Cartographer. Traveling in Scorpions, Warthogs, and captured Prowlers, John and other Marines located the Cartographer and learned that Truth was in the Installation's Citadel, a structure where the entire Halo Array could be activated. John then escaped from the Cartographer and proceeded to assault the fortress. After his arrival to Installation 00, John began to discover a number of terminals containing ancient Forerunner communications logs, as well as direct messages from the Forerunner ancilla Mendicant Bias.

John-117, Thel 'Vadam, and a squad of Marines were assigned to separately attack three barrier towers, which were emitting a protective shield around the Citadel. Although John and 'Vadam managed to deactivate two of the towers, Sergeant Johnson was captured at the third, spared only to activate the Halos from the Ark's Citadel. John, 'Vadam, and the Elites deactivated the last tower, lowering the shield. Just as the Shadow of Intent was about to destroy the Citadel, the Flood-controlled High Charity exited slipspace, bringing the Flood into the conflict and disabling the Shadow of Intent.

After defeating the last remnants of the Covenant forces around the Citadel, including two Scarabs, John and 'Vadam entered the Citadel. Although Miranda Keyes had forced her way in, breaking through the central window with her Pelican, she was soon surrounded. Knowing that only a Reclaimer could activate the Halo array, Johnson demanded that Keyes kill him, and then commit suicide to prevent galactic extinction. However, Keyes hesitated for a split second, during which Truth shot and killed Keyes with a Spiker. Truth then forced Johnson to begin the activation sequence for the array. In an unexpected turn of events, John and 'Vadam again made a temporary alliance with the Flood to stop the activation of the Halos. Truth's final unit of personal guards were crushed by the unlikely allies. As John and the Arbiter reached the Prophet, it was clear the San'Shyuum was already succumbing to the parasite. Thel 'Vadam executed the last of the High Prophets with his energy sword, while John deactivated the rings.

The Gravemind then betrayed John and 'Vadam, laughing as it had successfully used the pair again for its own ends. After fighting past waves of Flood, the two escaped with their lives. As they were leaving the Citadel, John saw a vision of Cortana that led him to the exit. There, he learned her plan: a replacement for Installation 04 had been built by the Ark, but was not yet connected with the rest of the Array. Since the Ark and the ring were so far from the inhabited galaxy, John decided to activate Installation 08 and destroy the Flood once and for all. But first, he headed to the remains of High Charity to keep a promise to Cortana.

On High Charity, John cut his way through hordes of Flood, taunted with images of Cortana falling into rampancy and by threats from the Gravemind itself. He finally reached the failing AI, on the verge of succumbing to the Flood's influence. After recovering her storage module, Cortana readied the Activation Index from the first Installation 04. John then destroyed the holy city by overloading its backup generators. On his way out, Cortana detected a friendly contact, which turned out to be Thel 'Vadam. High Charity exploded as the trio narrowly escaped on a Pelican.

Activating the Halo


"You are the child of my makers. Inheritor of all they left behind. You are Forerunner. But this ring...is mine."

- 343 Guilty Spark, betraying the Master Chief

The final mission of the war for John, 'Vadam, and Cortana was to destroy the Flood forever by activating the replacement Installation 04. The three landed on the Halo, discovering that the Gravemind had survived High Charity's destruction and was already trying to rebuild itself on the Installation. Flood dispersal pods released combat forms against John and the Arbiter, forcing them to fight their way up to the Control Room, where the ring could be activated. During the battle, Sergeant Johnson arrived and assisted the Chief.

After defeating the Flood forces around the Control Room, 343 Guilty Spark unlocked the door to the interior. Once inside, however, Guilty Spark realized that the team intended to fire the Halo before it could be completed, which would destroy the ring. Unable to cope with losing a second installation, 343 succumbed to rampancy. The AI mortally wounded Sergeant Johnson, and then turned on the Spartan.

John stood his ground, even after being hit by several energy blasts, and fought against Guilty Spark with all of his strength. Although the Monitor seemed to be invulnerable, Johnson shot the Monitor with a Spartan Laser, temporarily distracting him. He then handed John his weapon which seemingly destroyed Guilty Spark once and for all. Avery's injury was fatal, and he requested that his friend "send [him] out with a bang," after handing over Cortana's data chip.''

Cortana then activated Installation 08, and the survivors fled to the Forward Unto Dawn onboard a Warthog. As they fought the Flood and local Sentinels on the way, the Gravemind addressed them telepathically one last time, warning them that their victory would not spell total end for the Flood. The team boarded the Dawn and escaped the firing and destruction of ring and the Ark. However, the Slipspace portal the frigate opened could not sustain itself under the stress, and its closure severed the ship in half, sending 'Vadam to Earth. John and Cortana were left drifting in unknown space.

Missing in action
"Adm. Hood"

- Thel 'Vadam

John and Cortana were presumed dead after several months of searching by the Commander-in-Chief of the Office of Naval Intelligence, Admiral Margaret Parangosky. The forward half of the Forward Unto Dawn, bearing the Arbiter, crash-landed on Earth. On March 3, 2553, Lord Hood commissioned a memorial near Mount Kilimanjaro in Africa in honor of UNSC service members lost during the war. The ceremony was attended by John's closest folks - Dr. Catherine Halsey, SCPO Franklin Mendez and his comrades - Frederic-104, Kelly-087 and Linda-058, as well as by Naomi-010 and Serin Osman, formerly known as Serin-019. John's Spartan tag was carved onto the memorial by an unknown party and was accompanied by the improper insignia of the Master Chief Petty Officer of the Navy.

Stranded in space
"Wake me... when you need me."

- John's last words before entering cryostasis



Unknown to everybody else, John and Cortana managed to survive the explosion of Installation 08 in the remaining cargo portion of the Forward Unto Dawn, but it was nearly powerless and could not be properly navigated. Cortana, relieved that John had survived, explained this to the Chief, and that it could take years before anyone could discover their distress signal. In a similar conversation to one after the destruction of Installation 04, Cortana listed what John had done and told him, "It's finished," and this time, he agreed with her. John entered a cryotube, at which point Cortana stated that she would miss him. John replied her to wake him when she needed him.

In 2556, while still stranded in space, Cortana attempted to talk to John while he was still asleep. Unable to get a response from him, she recounted the history of the galaxy, seemingly unaware that John could not hear her, and showing major signs that she was descending into rampancy.

Requiem and the Didact
"Cortana"

- John-117

In July 2557, nearly five years after John went into cryo-sleep, the aft half of the Forward Unto Dawn entered orbit above Requiem, a Forerunner shield world. As Covenant forces near Requiem began to board the Dawn, Cortana awakened John from cryosleep. With Cortana's assistance, John fought off the intruders across the ship and used one of the ship's nuclear missiles to destroy an incoming Covenant cruiser. Shortly afterward, however, Requiem's access gateway opened, pulling the remains of the Dawn, as well as any Covenant ships in immediate proximity, into the interior of the shield world. Having crashed on Requiem, John took notice of Cortana's escalating signs of rampancy and she explained that her condition may be reversible if they managed to get to Earth and find Dr. Halsey in time. Fighting their way through numerous Covenant forces occupying the structure, John was attacked by advanced Forerunner combat constructs which Cortana identified as Prometheans. Evading or destroying pursuit, John attempted to warn the approaching of the dangerous gravity field that had disabled the Forward Unto Dawn.

After John disabled two energy pylons preventing them from contacting Infinity and attempted to use the supposed relay satellite in Requiem's core to establish contact, it became clear that a great threat had once been imprisoned within Requiem. Instead of contacting the Infinity, John had accidentally released the Didact, an ancient Forerunner warrior, from meditative hibernation within his Cryptum. Easily disabling John with his powerful abilities, the Didact declared the return of the Forerunners as the galaxy's rulers and saviors. Humanity remained weak and unworthy in his eyes of inheriting the Mantle of Responsibility. Having always revered the Forerunners as gods, the Covenant quickly swore alliance to the Didact and his armies. Tossing John aside, the Didact escaped Requiem's core using a slipspace rupture, an which destabilized the core.

Narrowly escaping the collapsing core facility, John and Cortana translocated to the planet's surface only to find their warning to the Infinity came too late. The massive warship crashed nearly 80 kilometers away, with a massive force of Covenant and Prometheans closing on their position. John was successful in regrouping with a group of Marines and Spartan-IVs, led by Commander Thomas Lasky, whom John had previously met on Circinius IV over thirty years earlier. Recognizing the Chief immediately, Lasky asked John and Cortana to clear a landing zone so that Infinity's ground forces could fall back to the ship which had fallen under siege. Commandeering a Scorpion tank, John led the attack to the crippled vessel alongside Commander Sarah Palmer's Spartans. Using the UNSC's latest weapon, the Mantis walker, John rallied a force of nearby Marines and regained control of the ship's interior. After reinitializing the ship's secondary MAC guns and missile batteries, the tide turned in the UNSC's favor and the Didact was forced to retreat.

Conflicting loyalties
"The Didact has to be stopped. If you won't do that... I will."

- John-117 to Captain Del Rio before disobeying his order

With a momentary lull in the fighting, John was called to a strategy meeting with Andrew Del Rio, Captain of the Infinity. Skeptical of the threat of the Prometheans, Rio ordered an immediate attack on a Forerunner gravity well preventing the ship from leaving. A strike force of Spartans led by John was deployed with a Mammoth ultra-heavy ground vehicle supporting the attack. Facing daunting odds, the UNSC was able to defeat a large armored strike force of Covenant and Prometheans and disabled the gravity beam. Diverted to an underground facility along the way, John was confronted with a vision from the Librarian, who warned him of the Didact's plans to enslave humanity with a device known as the Composer. The Librarian also provided John with a gift: a medical treatment to counteract the Forerunners' devolution of the human genome, and a means to resist the effects of the Composer.

Regrouping aboard the Infinity, Captain Del Rio dismissed the threat of the Prometheans and prepared the ship to depart the system. Defying direct orders, John took the increasingly unstable Cortana and departed the Infinity. Armed with a Pelican gunship provided by Commander Lasky, John launched several attacks on support pillars providing the Didact's Cryptum with shields and power, with the goal of preventing him from leaving the planet and attacking Earth and other colonies. John's attempt to stop the Didact ultimately proved unsuccessful, as the Didact managed to leave Requiem aboard his vessel, escorted by a flotilla of Covenant ships. Stowing away aboard a Lich, Master Chief pursued the Forerunner to Ivanoff Station, a UNSC research base orbiting Halo Installation 03 where the Composer was kept. Dr. Sandra Tillson, a lead researcher aboard the base, helped guide John to the artifact amidst a swarm of Covenant attackers. Despite John reaching the artifact first, the Didact was successful in obtaining the Composer and immediately tested the device on the crew of the station, completely destroying their bodies and assimilating their minds to power additional war machines. However, John survived, thanks to the genetic enhancements imposed by the Librarian.

Battle aboard Mantle's Approach
"You persist too long after your own defeat. Come then, Warrior. Have your resolution."

- Didact to Chief acknowledging his efforts to stop him

With the Didact approaching Earth, planning to imprison all of humanity into digital form, John pursued the Forerunner aboard an F-41 Broadsword fighter on the outer hull of the Promethean's ship. As the ship exited slipspace near Earth, John was surprised to find the Infinity and the rest of the Home Fleet ready and waiting for the Didact. John was able to destroy the ship's point defense guns, giving Infinity the chance to punch through the vessel's hull. Entering the breach, John fought his way to the Forerunner's location. Despite the UNSC's best efforts, the Didact was to fire on Earth with the Composer, digitizing the entire population of New Phoenix, Arizona. Armed with a HAVOK warhead, John confronted the Didact for the second time on a hard light bridge. While John was no match for the Forerunner's powerful abilities, the dying Cortana was able to immobilize the Didact with hard light shackles. The weakened John then planted a pulse grenade in the Didact's armor, blowing him off the bridge and sending him falling into a slipspace rupture underneath the Composer. With time having already run out, John detonated the nuclear bomb manually as a desperate last resort.

Using the last of her power, Cortana was able to save John from the blast, saving his life at the cost of her own. The two had one final conversation, with John remarking that he was supposed to have protected her. Cortana insisted that they were supposed to protect each other, and did. Smiling and seeming at peace, Cortana welcomed John home, and then faded away completely. Left adrift in space, John was recovered by a UNSC search-and-rescue team shortly afterward. Later, John spoke with now-Captain Lasky about the loss of his companion and the nature of their duty as soldiers. Aboard the Infinity, John rejoined Palmer and the other Spartans, and had his MJOLNIR Mark VI armor removed for the first time in several years.

The Composer's Forge
"You killed my friend. You killed millions of humans. You tried to kill me. I've tried to end you with blades, with guns, with explosives, by knocking you in slipspace... None of it works. I bet this does."

- John-117 confronting the Didact

On July 25, 2557 John was debriefed by the UNSC Security Council, though this questioning session as well as his survival were kept secret from Doctor Halsey. John confirmed that Cortana and the Composer were both destroyed over Earth, but he was unable to confirm the Didact's death. With there being no proof of a living Forerunner, the Council decided to tell the general public that the attack on New Phoenix was caused by the Covenant remnants and ended by the return of a hero, the Master Chief. Following his meeting with the Security Council, the Master Chief met with Lord Terrence Hood. Hood asked the Master Chief if he could advise a team on Installation 03 to investigate the loss of contact with a science team escorted by Spartan Black Team on the ring. The Master Chief then reunited with Blue Team, consisting of Fred-104, Kelly-087, and Linda-058.

John and the rest of Blue Team took a Longsword fighter to Gamma Halo and landed in near the science team's camp. There, the Spartans found the corpses of both the science team and Spartan Black. After being attacked by Promethean Knights, Blue Team discovered the former location of the Composer and within, the Composer's Abyss, a facility used to store the Composer's victims. The Spartans entered a slipspace portal at the end of the Abyss and were teleported to the Composer's Forge, housing six new Composers, where they were confronted by the Didact and his Promethean constructs. During the battle, 859 Static Carillon, the Forge's monitor, transported Installation 03 over the Forge by the Didact's request. The Didact subsequently took one of the Composers and departed for the Halo, intending to use the ring to eradicate humanity. Infuriated by the Didact bringing his "abominations" to the Composer's Forge, Static Carillon allied with the Spartans and escorted them back to the portal, holding off the hordes of Promethean machines.

Blue Team returned to the surface of Gamma Halo from the Composer's Abyss, arriving just in time as the Didact's new Composer rose from the pit. John fell behind while the Didact attacked and prepared to kill the others, starting with Kelly. Before he could do so, the Master Chief snuck up behind the Didact and stabbed him in the eye with his combat knife. Intending to correct his mistake of not having killed the Spartan when he had the chance, the Didact grabbed John by the helmet, lifted him up in the air and squeezed, cracking his visor. However, the rest of Blue Team intervened, forcing the Didact to throw John aside. The Forerunner quickly and easily subdued all four Spartans, but Static Carillon arrived and teleported the Didact into the Halo's control room before he could finish them off.

After recovering, John picked up the ring's Activation Index the Didact had dropped and intended to confront the Forerunner in the control room while the rest of the team returned to their Longsword. Using the Index to override the system's safeties, the Master Chief gave control of the Halo to Static Carillon who then ejected the section of the ring housing the control room, causing it to plunge toward the planet below. The monitor teleported John away just as the segment struck the Composer's Forge and the Didact was disintegrated by the Composers. John and Static Carillon materialized aboard Blue Team's Longsword, where the monitor bade farewell to the Reclaimer before departing to take Gamma Halo to an undisclosed location.

Self-reassignment
"Kelly-087"

- John-117

John returned to Earth with Blue Team where he was debriefed by Fleet Admiral Hood. While Lord Hood believed the Didact to be dead, the Master Chief considered it safer to call him "contained". Hood ordered John and the other Spartans to take a leave from combat, but upon returning to his team the Master Chief instead told them they were embarking on a new mission. In the following months, John led Blue Team on numerous classified operations, virtually without pause. These missions included diplomatic escorts through hostile territory, counter-piracy efforts against salvagers, and strikes against Covenant outposts. The Master Chief's determination to undertake mission after mission without rest was discussed by two high-level individuals within ONI, who deemed his self-reassignment a predictable consequence of his nature and unwavering dedication to his career. At some point amid these operations, John and Blue Team returned to the glassed Reach to remember Sam's sacrifice.

On September 26, 2557, two months after the New Phoenix Incident and Cortana's supposed death, a Beta-5 Division operative named Sapphire Three personally conducted an interview with John at Borneo Station, discussing his interactions with Cortana back in late 2552. She inquired him about Cortana's state at the time of her rescue on the Ark and about cryptic messages he had experienced while he was lightyears apart from her.

In early 2558, Blue Team was stationed at the construction site for a new ONI research facility, awaiting orders, when the facility came under attack by fanatical ex-Covenant. The hostiles managed to capture an M510 Mammoth, disable its governor, and drive it down a steep hillside toward the site's main fusion reactor. Blue Team followed in pursuit in an M12 Warthog LRV. John, Kelly, and Linda ejected from the Warthog when it was close enough to the Mammoth. The three of them managed to wrest control of the hulking vehicle from its hijackers. Kelly discovered scientists hiding inside the mammoth and relayed this to John, who was driving. Their presence meant he could not just drive it off a cliff, as doing so would almost certainly kill them. Instead, he steered it away from the reactor at the last second, but the near miss still resulted in the destruction of a decent amount of fabricated material that had been constructed. Kelly ensured that the scientists onboard were okay. The manager in charge of the construction project rushed over to Spartans after the smoke cleared and demanded to know who he should blame for the damage. John, who had taken the Mammoth's controls, took all responsibility for caused damage. The incredulous man accused the Master Chief of thinking he could get away with anything because of his status as a hero. At this moment, Fred jumped in to reprimand the thankless individual they had all just saved, finding it difficult to maintain an easy demeanor in the face of such disrespect. John kept a cooler head and directed the team to return to a nearby airstrip, as their next mission orders had come in.

Biko incident
"Every statue of him is a monument to be treasured"

- Senator Andrew Del Rio, referring to John-117 after his innocence at the Biko massacre was proven

In 2558 John and the rest of Blue Team discovered that an extremist organization known as Sapien Sunrise was planning an attack on Richard Sekibo on Biko. As a peace conference on Biko between the UEG and Sangheili representatives was coming to an end, John entered the embassy and instantly killed a member of Sapien Sunrise who was disguised as Richard Sekibo's bodyguard. A firefight began, in which a total of eighteen human lives were claimed. John fled the embassy alongside the Sangheili delegation, which he escorted to safety. Outside the embassy, the rest of Blue Team was waiting in an evac ship for John. Unfortunately, Sekibo was killed and John was unable to save him. His corpse was left behind in a field near the embassy on Biko. The next day, local officials discovered a signal beacon that led them to the body of Sekibo. After this event, the UEG and Biko government covered it up by making it appear that John had killed authorized bodyguards and Sekibo. This false story was spread throughout the inner colonies. The media started referring to John as "The Fallen Spartan". As Benjamin Giraud prepared to expose the cover up, and reveal the atrocities committed by the people behind the SPARTAN-II program, the UEG and Biko undercut him by radically reversing their claims, admitting and denouncing the involvement of Sapien Sunrise in the attack, utterly discrediting Giraud. Even Senator Andrew Del Rio, who had condemned the Master Chief in an official statement, reversed his position and took some immediate leave.

Argent Moon
"Fred-104"

- John-117

On October 23, 2558, John and the rest of Blue Team were deployed from the on a mission to find and secure Argent Moon, an ONI research vessel that had been missing for nineteen months. Departing from a D79-TC Pelican, Blue Team managed to infiltrate the Argent Moon by shooting out one of the windows, subsequently causing many Sangheili part of Jul 'Mdama's Covenant to be sucked out into the vacuum. Ascertaining that there were no human survivors aboard, John and the others fought towards central control, where they planned to disable the gravity and life support systems on the ship in order to kill off the rest of the Covenant. They were almost there when a Mgalekgolo destroyed a catwalk they were crossing and so fell multiple stories. While alone John experienced a vision from the Domain, with the image of Cortana telling him that it was open and that Meridian was next and the Reclamation was about to begin. He then was treated to a vision of a Guardian rising up from a bottomless chasm. Upon coming to, he found himself amongst Blue Team once more and told them what he had seen. Resolving to deal with it later, they continued onwards according to their original plan.

Upon witnessing Covenant vessels exiting slipspace all around the Argent Moon, however, the plan changed to asset denial and it was decided that the Argent Moon must be destroyed. Blue Team fought to the ship's reactor and disabled its safeties so that it would begin to overheat and detonate. However, the Argent Moon responded with automatic safeties, moving the reactor to a cooling center where it could be contained. Needing to ensure its overload, Blue Team followed the reactor to the cooling center in vacuum, using Banshees to destroy its coolant pipes. With their interference, the cooling system failed and the reactor began overheating, prepping Argent Moon ' s destruction. Blue Team needed to escape, but their Banshees would not escape the explosion in time and their arrival Pelican appeared to have been destroyed. John thus ordered them to the hangar where they could take a Winter-class prowler and escape into slipspace. Arriving at a hangar, the Spartans found the parked prowler ONI Acrisius, but needed to recharge its fuel cells. Many more Covenant attacked them while Blue Team defended themselves, waiting for the Prowler to prep for launch. With the hangar cleared and the Acrisius ready, John contacted the UNSC Infinity and informed them that he would be sending Blue Team to Meridian. However, Infinity was mysteriously already aware of Cortana's return and ordered John back to them while another Spartan team was sent to deal with her. Rejecting their orders, John and Blue Team chose to go AWOL and evacuated aboard the Acrisius, leaving the Argent Moon as it exploded.

Absent without leave


"Spartan Locke"

- John-117

The very next day, the UNSC declared John-117 AWOL. Fireteam Osiris, a Spartan-IV unit led by Spartan Jameson Locke, was tasked with recovering Blue Team and the Acrisius. Upon arriving at Meridian, Blue Team landed at Apogee Station and proceeded make their way downwards to where the dormant Guardian lay buried. Their arrival on-planet was witnessed by multiple colonists, who were wholly unaware of their intentions. Also unbeknownst to the people of Meridian was the fact that their own Governor Sloan purposefully ensured nobody tried to stop them, as he was already serving Cortana at that point. Blue Team encountered no resistance from the Warden Eternal or any mechanical Prometheans. Fireteam Osiris caught up to Blue Team as they were entering the Guardian and Spartan Locke ordered John to stand down and return to the UNSC peacefully. He told John that Cortana was their concern now. This caused John to lash out and begin a physical fight with Locke, as the rest of Fireteam Osiris looked on. He was able to overpower Locke and lock him in place with the armor restraint that had been meant for him. He then entered the Guardian without any more interruptions, and once he was aboard, it began to awaken. Fireteam Osiris scrambled to escape the collapsing chamber it had been held in as it rose out of the ground, carrying John and the rest of Blue Team. The Guardian caused massive amounts of destruction as it took to the air, both from the very fact that it was emerging from beneath the earth and from electromagnetic shockwaves it sent out continually. During this time, many mechanical Promethean forces were deployed from the Guardian to engage Fireteam Osiris as they tried to escape the destruction in their Pelican. The Guardian jumped to slipspace on a course for Genesis, taking Blue Team with it. In the wake of the emergence, John was declared KIA on Meridian by the UNSC two days later. It was thought that he was at least partly responsible for the civilian deaths caused by the Guardian on the planet, and it was decided an official story needed to be invented that did not reveal his AWOL status and Osiris' mission to hunt him and Blue Team down.

Genesis and revelation


"Stand down, Cortana. Come home with us. It's not too late to stop this."

- John trying to convince Cortana to stop

Upon landing on Genesis, Blue Team came across a series of computer consoles sounding musical tunes of Oly Oly Oxen Free. Following the path unlocked by interacting with those consoles, Blue Team battled through stranded Covenant forces before meeting the Warden Eternal. Shortly after learning of the Warden Eternal's role as Cortana's defender, John demanded to meet her, only for the Warden Eternal to refuse and commence hostilities. Shortly after Blue Team's defeat of the Warden Eternal in battle, Cortana finally revealed herself to them, expressing relief that they made it to Genesis. Upon questioning Cortana on the circumstances of her survival, they learned that the Domain had saved her; Cortana referred to it as the "water of life" for AIs. Suspicious of Cortana's desire to reunite with them, Blue Team proceeded further into the planet in order to physically locate her. Shortly afterward, Fireteam Osiris caught up with Blue Team. They warned John that Cortana was potentially dangerous, only for John to respond that he had already come to the same conclusion.

Before the two Spartan teams could team up, Cortana separated Blue Team from Osiris in separate parts of the installation. Blue Team fought an uphill battle through Promethean forces and multiple bodies of the Warden Eternal before physically meeting Cortana. There she revealed to them her plan to use the Guardians as a means of enforcing a forced peace upon the galaxy, giving sentient beings "a chance to be more than they are naturally". Comparing Cortana's behavior to that of Doctor Halsey's SPARTAN-II program, John pointed out a flaw in Cortana's plan: high collateral damage and a loss of free will. John pleaded with Cortana to stand down and return to Earth with the team. Cortana refused and forcibly sealed Blue Team in a Cryptum, intending to keep them in stasis for 10,000 years. With the aid of 031 Exuberant Witness, Fireteam Osiris narrowly managed to free Blue Team from the Cryptum. Upon his release, John asked Locke where Cortana was; Locke could only respond, "Gone, sir."

Following Cortana’s departure, both Blue Team and Fireteam Osiris together fought their way through hordes of Promethean constructs to reach a D79-TC Pelican that had previously arrived on the planet via a Guardian’s Slipspace entry. Based on Osiris' recommendation, John and his team agreed to return to Sanghelios; the joint team requested Witness’ help, who opened a Slipspace portal for them.

Reunion
"It took you long enough."

- Dr. Halsey upon meeting John for the first time in six years

Upon their arrival at Sanghelios, now mostly in the dark due to the Guardian attack at Sunaion, they correctly deduced they’d find their allies near the region of Nuusra. There they regrouped with Thel 'Vadam and his Swords of Sanghelios who had just destroyed the remaining cell of Jul 'Mdama's Covenant. In 'Vadam's field command post, John and Locke also met up with Spartan Commander Sarah Palmer and Dr. Catherine Halsey, whom John had not seen since before Operation: FIRST STRIKE in 2552.

Fake burial and legacy
In 2590, there was a ceremony for John-117 at an unspecified location near the areas of fighting during the Battle for Earth. However, his coffin is empty.

In 2607, the John-117 Monument began construction to commemorate the Spartan's service to mankind. In 2610, when the documentary Believe was being filmed, it had been over fifty years since the end of the Great War.

Personality and traits
"Our duty as soldiers is to protect humanity, whatever the cost."

- Master Chief about what it takes to protect human lives

Until the age of six, John lived a normal life with his family on the colony of Eridanus II. His conscription into the SPARTAN-II program was to shape much of his personality in the years to come. However, despite his difficulty relating to non-Spartan personnel, John nevertheless showed great depth of character throughout his many years of service.

As with all Spartans, John strives to win at any situation, at all costs. Although the drive to win was ingrained to the Spartans as part of their indoctrination, John appears to have possessed such an inclination even prior to his conscription; as a child, he would win at any game he played, including chess, gravball or King of the Hill. He is extremely determined to complete any mission at hand, and often disregards his personal safety to do so.

John is also noted for his exceptional luck, which, along with his combat skills and unyielding persistence, has allowed him to emerge victorious from situations many would consider impossible. Because of his many years of constant combat and military conditioning, John is not as emotional or sensitive as he once was, especially to fear. Although he is not devoid of fear, he simply acknowledges the feeling and puts it aside. He is calm in the face of danger but not foolhardy, as demonstrated during his first encounter with the Gravemind, when he warned the Arbiter that his arrogance was likely to get him killed. John is generally stoic and taciturn, but not devoid of a sense of humor and often makes dry remarks about the situation in hand to his teammates and allies.

On several instances, John has been forced to make tough decisions in order to achieve his goals, such as leaving behind his Spartan comrades on Reach or Cortana on High Charity, though he did come back on both occasions. More than once John had had to disobey orders to preserve human lives, as he did when he decided to keep Cortana to himself instead of surrendering her and pursue the Didact on his own. This decision proved right when the Didact was stopped before he could compose the entirety of Earth's population. The members of Fireteam Osiris, sent to recover John after he went AWOL, understood why he disobeyed the orders, and were confident that once the Chief discovered the truth behind Cortana's actions, he would do the right thing, as he always did.

He fully embraced his life as a soldier acting as a "shield and sword" for humanity in times of need. He feels no resentment towards Doctor Halsey because of his conscription, instead accepting the life imposed on him as a chance to live up to his full potential. As every Spartan, John has a strong sense of duty and commitment towards the UNSC. When he was asked by Warden Eternal that whenever "Cortana's Guardians are in motion and those who oppose her rule attempt to take back their worlds, will he help her to hold on to power or will he stand in defense of his own species?", John answered "Cortana knows the answer already".

He does not see himself as a superior being and fears for the lives of others before his own, putting himself in harm's way for the safety of civilians, and fellow soldiers, and does not judge others. Indeed, he is known to show an exceptional care for soldiers under his command and has shown great respect for the baseline humans he has fought alongside. An example of this is during the Battle of Installation 04. When making his way up to the Silent Cartographer, two Helljumpers, PFC Hosky and another Corporal, were killed by two Hunters. Afterward he regretted their loss, blaming himself for their deaths. This, and his reaction to Johnson's death on Installation 08 show that he does exhibit care and sympathy for soldiers under his command, even if he does do a good job of concealing his feelings. He never endangers the lives of those under his command if it is unnecessary. He would rather risk his own life instead of the others. As he did during the Battle of Circinius IV by drawing a Hunter's attention in order to give the cadets chance to run away, even with him running out of ammo. Deciding to follow Cortana's lead to Meridian on his own, John wanted to keep other Spartans from violating the UNSC regulations, though they decided otherwise and chose to remain by his side. He was also impressed by the humans who comprised his team following his escape from Installation 04, including Sheila Polaski and Corporal Locklear, both of whom he considered to have been worthy of being Spartans.

John is also known as a man of his word and will strive to keep any promise he makes, even at great personal risk. As he was forced to leave Cortana behind on High Charity, John promised to come back for her after dealing with the Prophet of Truth. Cortana chided him not to make a promise when he knew he couldn't keep it. However, despite incredible odds, John did keep his promise, as he fought his way through the Flood into High Charity to retrieve her. Upon finding her, Cortana was in a weak and damaged state. Unfazed, the Master Chief told her, "You know me. When I make a promise..." to which Cortana replied, "You keep it." This encouragement gave her the strength to compose herself after enduring the mental tortures of the Gravemind.

John's unfaltering, determined nature also serves to mask his feelings on many occasions, as he prefers to devote all attention to the goal at hand. He is cautious and observant, only making changes in his plans if they are of the utmost necessity. John is smart and noted for thinking outside the box, using unconventional means to reach his goal. He realizes his duty as a Spartan is to serve and help those in need, and can work professionally with anyone he is sent into battle with. Although John has difficulty understanding the 'undisciplined' lifestyle of civilians, he is fiercely protective of their lives and humanity as a whole. The mass slaughter of civilians at the hands of the Covenant was enough to drive even the stoic John into a cold rage. After the massacre on Draco III, John and his Spartans remained on-site until every Covenant soldier responsible for the atrocity was dead.

John greatly dislikes being kept in the dark, ambushes and fighting human soldiers. Once, when cornered by four large ODSTs in a gym, he did his best to avoid a confrontation. In the end, he was forced to defend himself with lethal force. While killing Covenant never placed a burden of guilt on John, ending the lives of fellow human beings was something he never felt comfortable remembering. Also John, as with many Spartan-IIs, hates space battles, as being stuck on a spaceship during a space battle makes him feel helpless. As a soldier, John knows when it is appropriate and inappropriate to fight, and has great control over his emotions thanks to a clear state of mind. Due to his augmentations, he reacts much faster than an average human, seeing events at a fraction of normal speed. It is almost a clairvoyant state of mind, and as a result of this, has an acute intuitive insight and perception of any situation combat or non-combat. He has been known to have vivid and long-enduring memories of the past, such as in dreams. No matter how well-adjusted he is, however, John always seems to need to have a quiet place away from crowds after a battle in order to feel at peace.

While reflecting on his life during his battle with the Didact John stated that he did not remember anything from his childhood from before his conscription: not his name, his family, his home, except the King of the Hill game he played with the other children in his school's playground. Through thirty years of warfare he was always prepared to die in battle, but when he was about to die by Didact's hand on Gamma Halo, he discovered he was not ready to die. After defeating the Didact, John continued to obsessively embark on new missions even after receiving an R&R order from Lord Hood.

Leadership
"Of course, John volunteered. He was always the first to explore the unknown for the rest of us."

- Kelly about John's decision to test Mjolnir armor

Throughout his training, John proved himself as one of the most promising leaders among Spartans, and Dr. Halsey considered him the best candidate in the entire program. His aspiration to win and his care of his teammates eventually helped him gain the position of squad leader. In years to come, many Spartan fireteams emerged with their own leaders. John took command of Blue Team, though he kept his commander role for the whole SPARTAN-II company.

As a senior Spartan, John took his responsibilities very seriously. After the augmentation procedures that took lives of nearly a half of Spartans, John was devastated; observing how his crippled brothers and sisters were transferred to other UNSC divisions almost made him furious. He did not want to lose them, though he understood that they could no longer fight alongside him. John was the one who volunteered to test Mjolnir armor even after Dr. Halsey confirmed that all previous testers died in process. Being a leader, John would not order his men to do what he could not do in the first place. He was always confident in his men's capabilities, suggesting the most proficient ways to solve the matter, which were considered by non-Spartan personnel as suicide.

What affected John the most were the deaths of people under his command; John considered every Spartan lost during the war as his own mistake, swearing to become stronger the next time. During the Fall of Reach, John lost contact with his Spartans, however, he was sure that some of them survived the glassing and was determined to save as many as he could. More than once John took command of mixed units or squads consisting of Marines. He was capable to organize them to act as a Spartan fireteam, achieving despite almost impossible odds. On Requiem, during the initial engagements between UNSC and Promethean forces, John assumed tactical command of Infinity ' s ground forces including Spartan-IVs, despite being outranked by many of them. Upon his return to Blue Team, Fred-104 ceded command to John despite outranking him by two ranks. Blue Team also willingly followed John when he chose to go AWOL.

Reputation
"Folks need heroes, Chief, to give 'em hope, so smile would ya, while we still got something to smile about!"

- Avery Johnson to John upon entering Cairo Station's bridge for receiving badges.

After the end of Human-Covenant War, John became an icon as a soldier who had played a pivotal role in ending the decades-long war and in doing seemingly gave his life. He was lauded as representing the ideal of a human soldier by UNSC propaganda, a view embraced by many among the general population. Considering John his personal hero, journalist Benjamin Giraud attempted to find out about his background and personal history. When John was declared dead, on many human worlds statues were built in his honor. Private companies started selling action figures in John's likeness; Gabriel Thorne's grandmother bought one after he was recruited into the SPARTAN-IV program. During his military career John served as a source of inspiration and morale booster for others whenever he was on a battlefield. Chief's determination and selflessness made Thomas Lasky, then a young, doubtful cadet, dedicate his life to military service, eventually reaching the position of commanding officer of the most advanced human ship. With the development of SPARTAN-IV program many soldiers enlisted with Spartans to be like the legendary "Master Chief". Such as Gabriel Thorne, who enlisted believing the Spartans were special, and that had he been one, he could have saved his family in New Phoenix. Years later, when the UNSC discovered that the Chief actually survived and managed to prevent the Didact from enslaving the entire human race, they decided to cover it up as a Covenant remnant attack which was successfully fended off via perfectly timed return of the UNSC's greatest hero, thus again underlining the Spartan's supposed invulnerability. However, when Chief decided to go AWOL the UNSC declared him KIA during Battle of Meridian in order to hide his status and preserve his reputation.

Because of his reputation and experience, John's de facto authority far surpasses his nominal rank, and UNSC personnel of all levels are known to defer to his experience and charisma. When Lord Hood offered John a commission, even suggesting he could be conferred the rank of admiral, the Master Chief jokingly replied, "The Admiral doesn't have quite the same ring to it". At the time of his going AWOL in October 2558, Spartan Sarah Palmer implied that John and Blue Team had been operating essentially independently for some time, commenting that "He does what he wants". When the Master Chief chose to defy orders to go after the Didact, Lasky and Palmer visibly made no effort to arrest him as ordered by Captain Del Rio and Lasky defied orders to help the Master Chief directly as he trusted him enough to not take the risk the Master Chief was wrong.

In the eyes of the Covenant, John-117 was branded as The Demon and was considered the main nemesis of the entire Covenant, with most of the Covenant fearful of his presence. Thel 'Vadam stated that the personal title emblazoned on John-117 was an insult, but also held a modicum of respect. The Covenant respected him in terms of his strength and how he was able to defeat thousands of Covenant troops effortlessly, with even Thel 'Vadam at the time unable to stop him from destroying Installation 04. Despite the Covenant's dissolution following the Prophet of Truth's death, John-117's nickname as a demon remains in use by many former members of the Covenant.

Relationships
"The thing about John is that he only really knew three ways to react to people. If you were his superior officer, he obeyed you. If you were in his squad, he would die for you. But if you were a threat, then God help you."

- Samuel-034 about John's behavior

John does not open easily to strangers, and has notably shown an aversion to taking his helmet off in the presence of others unless necessary. Friendships are made for life, however—once given, his trust is forever. Like most Spartan-IIs, he thinks of Doctor Catherine Halsey as a nearly mother-like figure, and holds a deep personal respect for his trainer and mentor SCPO Franklin Mendez. His fellow Spartan-IIs, Cortana, Dr. Halsey, and SCPO Mendez, being the only family he really ever had, assume a larger-than-life importance for John-117.

John formed close friendships with the other Spartans he grew up with since his childhood, most notably Samuel-034 and Kelly-087, his first friends within the group. While still feeling the loss of comrades deeply, he has grown more accustomed to combat than most soldiers. Nevertheless, he was deeply affected by the deaths of each of the Spartans, particularly Sam. He was also saddened by Linda-058's apparent death aboard Gamma Station and was greatly relieved after Dr. Halsey successfully resuscitated her. However, having accepted the responsibility of command for the Spartan-IIs, he has come to maintain a certain professional distance to his comrades and mostly keeps his feelings to himself to maintain his authority.

Cortana
"We were supposed to take care of each other. And we did."

- Cortana to John moments before perishing

In a strange twist of fate, John-117 built a close friendship with the AI Cortana, a construct "born" from the mind of Dr. Halsey herself. Despite some initial hesitation towards working with an AI out of fear of conflicting directives, John and Cortana quickly formed a formidable team. After a near-fatal training exercise masterminded by ONI Colonel Ackerson, John realized that Cortana would be a great help instead of a liability. During their exploits on Installation 04 and afterward, John displayed a firm trust in Cortana, even believing in her when Lord Hood was unsure of the reliability of her word that she had a way to stop the Flood. Years later, on Requiem, he went as far as to disobey a direct order to give her up for decommissioning. Cortana ultimately sacrificed herself to save him and John was clearly upset by her death. Her death made him ponder what it really means to be human.

After being made aware of her potential survival the Chief again disobeyed an order to return to the UNSC and sought to investigate the situation himself. After witnessing firsthand the terrible aftermath of Cortana's awakening of the Guardians, he refrained from making any premature conclusions about her involvement until reestablishing contact with the AI. However once arriving at the Forerunner world of Genesis and having several evasive conversations with her, the Master Chief grew suspicious of Cortana's motives, to the point of having to verbally call her out on attempting to use their past friendship as a means to manipulate him. When Cortana eventually divulged her plans to use the Guardians as a forceful instrument against those who will oppose her rule, John made one final attempt to talk her into standing down peacefully and return home. His efforts proved unsuccessful, and he was forcibly locked into a Cryptum along with the rest of Blue Team by Cortana; ultimately being rescued by Fireteam Osiris shortly after.

Thel 'Vadam
"Jameson Locke"

- Thel 'Vadam

John and Thel 'Vadam's first meeting on Delta Halo was hostile, with the Arbiter continually referring to the Spartan as "Demon" and John's insistence that the San'Shyuum were making a "big mistake" by activating the Halo rings. Upon their next meeting on Earth, John was quick to try and kill the Sangheili before Johnson stopped him. They remained initially wary of one another, but learned to trust each other in combat against the Covenant and the Flood. Thel proved his trustworthiness to John through actions such as assisting him in the rescue of Sergeant Johnson, or counseling his fellow Sangheili not to glass all of Earth after the Flood outbreak at Voi. When they reached the Ark, the two's reliance on each other was cemented, and John demonstrated his respect for Thel by allowing him be the one to kill the Prophet of Truth. The Arbiter also came to his aid on High Charity despite having little need to do so, and chose to fight with John to the end in his efforts to stop the Flood and consoled him on Johnson's death. 'Vadam was the last one to see John alive before the latter went missing after the war, and afterward expressed to Lord Hood mild doubt that John might be dead. 'Vadam would later refer to John as a "friend", and upon learning that he was still alive following the events on Ealen IV, Thel believed that he was the key to the galaxy's future. During the Battle of Sunaion, Thel referred to the Chief as the greatest of all Spartans, and later asked Spartan Locke to give the Chief his greetings.

Sergeant Major Avery Johnson
In the final months of the Covenant War, John developed a comradeship with the veteran UNSC Marine Avery Johnson. The two fought side-by-side in several battles, from Reach to Installation 04 to Earth, the campaign on Delta Halo, as well as on the Ark where Johnson would ultimately meet his end by 343 Guilty Spark. The Master Chief and Johnson cared greatly about one another, and 117 trusted Johnson without doubt as seen when he allowed Johnson to take Cortana to be inserted in Installation 08's Core. Following Johnson's death, John was visibly saddened.

Age and appearance
John has "...short hair, with serious eyes, a firm mouth, and a strong jaw." His skin is unnaturally pale since he has spent most of his life in his armor. Shortly before his abduction at the age of six, John was "a typical six-year-old male, with tousled brown hair and a sly smile that revealed a gap between his front teeth".

John's age is affected by the same ambiguities as all beings who undergo extended voyages through space. Though he is chronologically 47 years old as of mid-2558, he has spent much of his life in cryosleep, particularly when he spent almost five years adrift aboard Forward Unto Dawn. Cellular activity is slowed to near standstill in cryosleep, effectively halting the aging process. As a result, John's biological age is less than his age as measured by Terran chronology.

Equipment
"Dr. Halsey"

- John-117

Throughout his career, John has shown a preference for the standard-issue set of the given Mjolnir armor generation used at the time. His Mjolnir armor is invariably colored olive green with a gold visor, which has made his appearance iconic among humans and Covenant alike. At some point during his four-year cryosleep aboard the Forward Unto Dawn, Cortana used nanomachines to repair and physically alter John's MJOLNIR Mark VI armor. Cortana also rewrote the suit's firmware, altering the HUD as well as improving the suit's shield-recharge rate and its compatibility with Covenant and Forerunner armor plugins. His upgraded suit displays the Braille characters "117" on the left of the breastplate.

Immediately after the Mission to Installation 03, John received an upgrade for his Mark VI armor from ONI's Watershed Division, bringing it into the GEN2 line of Mjolnir PAA. The armor still looks like his updated GEN1 Mark VI, the most prominent difference being a redesigned bodysuit. His armor also now lacks the prominent gash on the chestplate and his helmet is intact again after the Didact severely damaged it during Blue Team's battle against him on Installation 03. His visor was once again cracked by Spartan Jameson Locke on Meridian.

John's old Mark IV helmet is used as the "last thing" that SPARTAN-IV candidates see before beginning their evaluation and preliminary augmentation cycle.

Production notes

 * John is the protagonist and main playable character throughout the core of the Halo series. He is voiced by Steve Downes in the original trilogy, the Reclaimer Saga, Halo: Reach's Firefight mode, and the audio version of "Palace Hotel". In the Halo Legends shorts "The Package" and "Odd One Out", John is voiced by David Wald. In Halo 4: Forward Unto Dawn, he is physically portrayed by Daniel Cudmore, who is known for portraying the mutant Colossus in the X-Men film series, while provides his voice. Bruce Thomas provided John's motion capture performance in Halo 4 and apparently served as the model for his face in the game's Legendary ending.
 * John-117 is likely named for Sylvester Stallone's character John Spartan, from the 1993 action film Demolition Man. Spartan is placed in cryostasis before awakening decades later, much like how John-117 is introduced emerging from cryosleep in Halo: Combat Evolved.
 * John appears as an Easter egg in Halo: Reach, asleep inside a cryo pod in the Pillar of Autumn's hangar.
 * Late in the development of Halo: Combat Evolved, (when the game was known simply as Halo) Microsoft urged Bungie to change the main character's title from "the Master Chief" to "the Commando", as they felt that it better suited the tone of the game.
 * In Halo 5: Guardians, John-117's character-specific base attributes are increased melee damage and faster shield and health regeneration rates. His default weapons loadout includes an MA5D assault rifle, an M6H2 magnum, and two fragmentation grenades.

Trivia

 * A tower in the shape of John's helmet can be found on Mars in Bungie's Destiny.
 * Fable II makes a reference to the Master Chief with a character of legend named "Hal", also called the Minstrel Chief. The armor featured (clearly inspired by Halo's MJOLNIR Powered Assault Armor) is known as "Hal's Armor". A sword resembling the Energy Sword is also featured in the game, known as "Hal's Sword". In addition, with the Special Edition, the player can obtain the title "Master Chief" for their hero for free from any title vendor.
 * A wax sculpture of the Master Chief is on display at Madame Tussauds in Los Angeles and Amsterdam. He is the first video game character to receive a Madame Tussaud's wax sculpture.
 * John's surname is consistently unknown. However, because his redacted name in the Eridanus II census record takes up less space than the surnames of Rolla Hedegaard and Hirayama Tatsuyuki, it can be determined that his surname is less than nine letters long.