John-117

* SPARTAN-II Program
* UNSC Special Forces
 Rank
 Era
 Height
 Eye Color
 Hair Color
 Skin Color

Master Chief Petty Officer **John-117** (surname classified), better known to the public and to history as the **Master Chief**, was a human male who lived in the 26th century. He was a SPARTAN-II commando of the UNSC Navy's Special Weapons division. He served as one of the most important figures of the Human-Covenant War and in human and even galactic history. After nearly thirty years of active duty, he was 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 except the Prisoner of War Medallion.

For much of his career, John served as the leader of SPARTAN-II Blue Team. As the Human-Covenant 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 Protheans to destroy their parasitic enemy, the Flood, by killing all life in the galaxy. Having destroyed Halo, the surrounding Covenant fleet, and the Flood forces on the ring, John-117 returned to Earth and resisted the Covenant's impromptu invasion. Pursuing the invaders' flagship, the Master Chief encountered Installation 05, where 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 in action 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 Covenant devotees, beginning on the shield world Requiem. This culminated in an attack on Earth and the Didact's temporary defeat, as well as the loss of Cortana. John subsequently reunited with Blue Team and with their help, vanquished the Didact for the second time. John and his Spartan compatriots then departed Earth to embark on new missions, eventually falling out of contact with the UNSC.

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 is regarded by the Covenant (apart from those allied with humanity) as a "Demon;" however, John specifically is known as "*the* Demon", an epithet he earned after the destruction of Installation 04. Allied Sangheili like Arbiter Thel 'Vadam and Shipmaster Rtas 'Vadum have referred him simply as "Spartan".

## Early childhood

Born on March 7, 2511, John lived with his mother and father in Elysium City, on the colony world of Eridanus II. He attended the Elysium City Primary Education Facility Number 119. As a child, John had brown hair, freckles, and a small gap between his front teeth. In a memory, John recalled that his mother was kind and smelled of soap. The would-be UNSC Marine Lieutenant Parisa was a childhood friend of John's. John once saved her from drowning at Lake Gusev, after which John promised to marry her and keep her safe. A photo of the two was also taken by Parisa's father soon after, and would be kept as a memory by Parisa long after she thought John had passed away. He also was a friend of Ellie Bloom, living next to each other in their childhood, and Katrina, who played obstacle race with him and Ellie.

At the age of six, he was identified by Dr. Catherine Halsey as one of 150 preliminary candidates for the SPARTAN-II program. John was an ideal physical and mental candidate, standing a head taller than the majority of his schoolmates, having greater physical proportions, possessing greater strength, exhibiting superior reflexes, and having an aggressive drive for success. By the time he was conscripted, he had a string of forty-five victories in what Dr. Halsey referred to as a "brutal version" of the game of *King of the Hill*, resulting in him having a chipped tooth and his opponents suffering various bone fractures.

In response to the covered-up Flood attacks on Luna in 2513, production of the SPARTAN-II Program was rushed even further. Halsey was forced to isolated candidates not only on their genetic makeup, but also by their resilience against disease and viral infection. In his youth, John was only sick once with a severe case of the flu.

When Dr. Halsey and Lieutenant Junior Grade Jacob Keyes visited Eridanus II in 2517 to study him, they were impressed with his intellect and luck. In a final test of his viability as a candidate, he was asked to determine which side an old coin would land on. He watched the coin as it flew in the air and caught it before it could land; correctly stating which side was face-up, on the side of the eagle. Later that same year, John and 74 other six-year-old children were conscripted to the planet Reach: they were covertly kidnapped from their homes and replaced with flash clones to cover up the kidnappings. All of the clones would later die of seemingly natural causes as a result of their accelerated growth process, with John's flash-clone dying on December 7, 2517.

## Spartan training

*Main article: SPARTAN-II training*
John and the rest of the children chosen for the SPARTAN-II program were brought in 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 the 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 only friends among the trainees for most of his life. 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. After being scolded by Mendez, he quickly quit the practice. Indeed, John would quickly become much more reserved, quiet and goal-focused in the following years, abandoning his more colorful childhood personality.

John quickly proved himself to be considered 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 Frederic-104. Dr. Halsey believed John held both the skills and natural ability to lead the entire Spartan-II group. CPO Mendez disagreed with her assessment, instead believing Kurt would fulfill the role as team leader. John's leadership skills were correctly observed, as the result from their mission clearly solidified his role as the overall leader of the SPARTAN-IIs. He also became the established leader of SPARTAN-IIs Blue Team.

### Taking the initiative

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. John refused. After organizing them, the Spartans looked to him as their leader. It was a role he was surprised to be given, but quickly accepted, illustrating his evolving get-it-done personality. 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 the AI Déjà, and attacked the guards with stones, killing them. Chief Mendez was not initially pleased, feeling John had violated the boundaries of the test and permitted unnecessary casualties. 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.

### SPARTAN physical augmentation

At the age of 14, John and the other Spartans 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 into the Office of Naval Intelligence. Even before his cybernetic and genetic augmentation, at 14 years of age, due to superior genetics, John had a physical body of an 18-year old Olympic athlete. Far beyond the physical alternations, 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 UNSC *Atlas* 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 orders of the sergeant 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.

## Insurrection service

*Main article: Assault on Eridanus Secundus*

John-117's first mission was during the Insurrection Wars. The Spartans were pitted against Insurrectionists within the asteroid belt of the Eridanus system, where his homeworld was located. He was shot in the side while leading his squad to capture the rebel leader Colonel Robert Watts. The official results of the mission listed eleven dead enemy soldiers and an unknown number of rebel civilians. He received a Purple Heart upon the completion of the mission for taking a round in the side.

## Battle of Chi Ceti IV

*Main article: Battle of Chi Ceti*

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 Empire. A short time later, the UNSC *Commonwealth*, under the command of Captain Wallace, brought the Spartans and Dr. Halsey to the Damascus Testing Facility at Chi Ceti, where they recieved their MJOLNIR Mark IV Powered Assault 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 and only friends. The victory showed humanity that the Covenant could be beaten, but only at a high cost.

## Battle of Circinius IV

*Main article: Fall of Circinius IV*

In 2526, John, Kelly and Fred-104 were sent to support Marine forces in a search-and-capture mission against an Insurrectionist leader; the skirmish quickly escalated as the Covenant's arrival forced the UNSC troops to briefly side with the rebels. Sometime later, he and Blue Team were sent to Circinius IV to reinforce the UNSC's defenses there. The Spartans eventually received a distress signal from a cadet squad pinned down at the Corbulo Academy of Military Science. John defeated the Sangheili Zealot that had been pursuing the squad, and radioed Kelly to rendezvous with him and the survivors at an extraction point up north. John, who identified himself only as "Master Chief", cleared the way to the deceased General Black's Warthog and ordered Cadet Thomas Lasky to drive.

The team was ambushed by Jackals while en route to the Pelican, causing irreparable damage to the Warthog. The team continued on foot and were relentlessly pursued by a pair of Hunters. One Hunter was killed in the ensuing battle, but in the process the squad was left with only stun rounds. John planned to put himself in the line of fire, while the cadets ran for the extraction point. However, Cadet Lasky, motivated by the death of Cadet Chyler Silva, took the Master Chief's place. The remaining Hunter fired at Lasky while John planted his last grenade inside the Mgalekgolo's worm colony-body. After rejoining Fred and Kelly aboard a Pelican dropship, John gave Lasky an armor fragment from the Hunter and commended the cadet on his bravery. Lasky kept the shard as a memento of the battle. He would not meet John again until 2557 on the planet Requiem. John would latch onto the term "Master Chief" (his actual rank), and would eventually become known primarily under that alias.

## Later war service

John participated in the Harvest campaign in early 2531, where he encountered the body of fellow Spartan Daisy-023. Later that year, he led Blue Team in a raid against Camp New Hope on Victoria; Blue Team had been disrupting assets from General Howard Graves' Insurrectionists cell. John and most of the other Spartans were captured, though they were soon rescued by Kurt-051; their escape inadvertently led to Graves' death. John led Blue Team during the Battle of Jericho VII in 2535, where they killed thousands of Covenant soldiers with a HAVOK tactical nuclear weapon.

## Operation: WARM BLANKET

*Main article: Operation: WARM BLANKET*

Shortly after the Battle of Miridem in 2544, John, along with Fred-104, Kelly-087, Solomon-069 and Arthur-079, was part of a mission to rescue Dr. Catherine Halsey from a Covenant fleet. The team utilized several advanced prototypes during the operation, including MJOLNIR Mark IVb armor, MA5C assault rifle prototypes, and OF92/EVA "Booster Frame" fighters, which were designed for ship boarding actions, and infiltrated the assault carrier *Resplendent Fervor*. While clearing the assault carrier, John encountered Sangheili Major, Thel 'Lodamee, who challenged John to an energy sword duel. Near victory, Thel was forced out of the duel when his Fleet Master Luro 'Taralumee separated the lower section of the assault carrier to kill the Spartans, recalling him back into the upper section. Both soldiers were left with their battle unfinished. The Spartans completed their mission and rescued Dr. Halsey, but Arthur and Solomon were killed in the battle. John was saddened by his teammates' deaths and swore he would become stronger, vowing to keep his comrades alive at all costs.

### Sigma Octanus IV

*Main article: Battle of Sigma Octanus IV*
By summer of 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, arrived at the city Côte d'Azur to detonate a HAVOK nuclear warhead to clear Covenant forces from the city. 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 UNSC *Iroquois*, which brought them back to Reach.

### Fall of Reach

*Main article: Fall of Reach*

On August 29, 2552, during the Covenant's ongoing invasion of Reach, 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 eventually 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 SPARTANs were deployed to protect the generators which powered Reach's twenty Orbital Defense Platforms. John, along with Linda-058 and James-005, was sent to *Gamma Station* to destroy an unsecured navigation database onboard the prowler UNSC *Circumference*. 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, unbeknownst to John, was in fact a fellow SPARTAN from Project: ORION. The team returned to the UNSC *Pillar of Autumn* and was placed into cryo-sleep as the ship landed on and later fled Reach, and, following the Cole Protocol, jumped into warpspace. 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

*Main article: Battle of Installation 04*

Arriving at Prothean Installation 04, it soon became clear that the *Halcyon*-class cruiser UNSC *Pillar of Autumn* had been followed through warpspace 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 unidentified ring. Keyes was, however, captured almost immediately after landing by the Covenant fleet, being interrogated for classified ONI intelligence. The rest of the surviving command crew was captured as well, but were presumably executed for not possessing vital knowledge.

The surviving human personnel launched a mission to recover Captain Keyes, who was being held aboard the CCS-class battlecruiser *Truth and Reconciliation*. Under the cover of night, John-117 and a fireteam of Marines and ODSTs boarded the ship via its gravity lift. After several brief engagements aboard the ship, the rescue team managed to establish a secure control of the ship's command center. John-117 went ahead and freed Captain Keyes and several other captured Marines. When they returned to the command center, they found out that the Marines and ODSTs have been slaughtered by Stealth Sangheili. Furthermore, Echo 419 was unable to retrieve the rescue party due to Covenant air patrols. Following Cortana's suggestion, Captain Keyes manned a Covenant Spirit dropship and returned everyone to Alpha Base.

The battle of Installation 04 quickly degenerated for the human forces, resulting in almost 75% casualties a few days into the conflict. Most of the scattered Marines cut off from Alpha Base would be picked off and killed by Covenant forces. Master Chief was remotely dispatched to evacuate a squad of ODSTs who were pinned-down by Brutes near a Prothean cliffside bunker. After another brief skirmish, the squad was evacuated, suffering minimal losses.

Using the intelligence gathered by Captain Keyes and Cortana, the human forces amassed a squadron for an assault on the Silent Cartographer island, in their attempt to uncover the location of the Installation's Map Room. John-117 and a Marine assault team, supported by *Echo 419* and *Bravo 022*, penetrated the Covenant defenses, journeyed deep within the island's chambers and access-ways, and discovered the location of the Installation's control room. Events leading to the discovery was not easy; the Covenant managed to temporarily lock access to the chambers within the island, prompting John-117 and the Marines to navigate to the island's security chamber. As they deactivated the security, Bravo 22 and its payload fell prey to Covenant fire.

    After the Battle of the Silent Cartographer, Cortana instructed Foe Hammer to deploy them using navigations she gathered from the discovery of the control room. Alone, John-117 was inserted into a network of tunnels occupied by Covenant forces. The Spartan then received a radio transmission from Fire Team Zulu, who were pinned down in a valley, as he fought his way through the network of tunnels. John-117 assisted Fire Team Zulu in eliminating local Covenant forces and their armor support, then journeyed through a system of adjacent canyons until reaching a dead end, where Fire Team Zulu requested to be evacuated. John-117, with Cortana providing guidance, eventually discovered a large pyramidal structure bulit into a cliff, on top of which was the control room. Upon reaching the chamber, Cortana accessed the Installation's systems and discovered a terrible secret quarantined within the Installation. Fearing for Captain Keyes' safety, she instructed John-117 to head to his last known location.

Believing himself to be perhaps the only surviving SPARTAN-II, John committed himself to the destruction of any Covenant unit unfortunate enough to encounter him. 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-117 was sent out by the Installation's monitor, 343 Guilty Spark, to retrieve the Firing Index, an activation device for the Halo ring. Seeing the danger posed by the Flood first hand, John willfully took up the role as the Installation's "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 organic 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 between the Covenant, the Flood and the Prothean's 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* once again, 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-117 used a Warthog to reach the extraction point where Pelican *Echo 419* was to recover him. John-117 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 went critical, destroying the ring.

### Return to Reach

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 then-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 the charred remains of 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.

### Operation: FIRST STRIKE

*Main article: Operation: FIRST STRIKE*

John and remaining SPARTAN-IIs Linda-058, Grace-093, William-043, and Frederic-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, 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 Prothean 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 Sgt. 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.

### Covenant Invasion of Earth

*Main article: Covenant Invasion of Earth*

Once back in Earth orbit aboard *Cairo Station*, John received the MJOLNIR Mark VI Powered Assault Armor and attended an awards ceremony with Miranda Keyes and now-Sergeant Major Johnson. The ceremony was interrupted by the arrival of the Covenant Fleet of Sacred Consecration, initiating the Covenant Invasion of Earth. Upon discovering a Covenant antimatter charge on board *Cairo Station*, Master Chief 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, Chief 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 him 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 UNSC *In Amber Clad* quickly recovered the free-falling Spartan.

Chief was then deployed to the surface battle in 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 Scarab. Chief, Johnson 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 wall of alien occupiers.

After intense fighting through numerous highway tunnels and suburbs, John reached the industrial zone, where Marines under the command of Staff 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 back to *In Amber Clad* to intercept the Prophet of Regret's flagship. When the flagship started to enter warpspace in-atmosphere, Lieutenant Commander Keyes was granted permission by Lord Hood to follow it, arriving just in time before a catastrophic warpspace-explosion destroyed most of New Mombasa. John, and all on board *In Amber Clad*, were transported to Installation 05.

### Installation 05

*Main article: Battle of Installation 05*

Forced to act quickly at Installation 05, John was deployed groundside in an SOEIV along with several Orbital Drop Shock Trooper squads. Cortana told John of the Prophet of Regret's intent to fire the new 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 warpspace, followed by *High Charity*, the Covenant's holy city. Quickly disposing of a force of Sangheili Honor Guards, John assassinated the Prophet via a brutal bludgeoning with his armored fists 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 new Arbiter Thel 'Vadam 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 this ring's 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. Just then, a Flood-infected *In Amber Clad* would warp inside *High Charity*, forsaking the already war torn city. A dying Prophet of Mercy, compromised by a Flood infection form, cackled that Truth had ordered his Dreadnought to Earth where he would complete the destruction of the human race. John then crushed the infection form 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 Prothean Dreadnought, but not before promising to return for Cortana after he stopped the Covenant.

### Battle aboard the Dreadnought

John-117 stowed aboard the Prothean Dreadnought without incident for quite some time, while tracking Truth's movements aboard the ship. When the Dreadnought entered the Sol system and passed Jupiter, he 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 eventually found himself faced by an extremely large force of Covenant troops in another part of the ship. He fell to the floor after being hit by several assault cannon beams, compromising his energy shields and breaching his armor. Weakened, he is confronted by a Brute Chieftain who begins to interrogate him about the Key of Osanalan, an object that he has no knowledge of. However, the Spartan sticks the Brute with a plasma grenade and escapes.

Chief then continues to push through the ship, eventually arriving in the prophets chambers and setting his sights on Truth. He proceeds to hold up his carbine, with his sights set on the Prophet, and fires a round. However, the Prophet is protected by shields and the Spartan is shot in the back by a Jackal. He falls several stories and lands right in front of the Prophet's Brute Honor guards. While John manages to get several shots at Truth, he soon makes his escape, as John is left to fight the guards. Grabbing one of the Brute's gravity hammers, he kills them all and starts to find a way off the ship.

Having failed in his attempt to assassinate Truth, John blasts his way out of the Prothean ship's airlock in a Covenant Ghost. Just as the ship enters Earth orbit, he is contacted by Lord Terrence Hood. Upon being asked what he is doing on the ship, John simply says he is "*finishing the fight*".Once on the outer surface of the Dreadnought, he is informed that the command ship holding the "key" is to be destroyed, and that he will be within the radius of the blast unless he takes immediate evasive maneuvers. He moves to another part of the Prothean ship to avoid being caught in the blast's wake. John-117 is then ordered to find a way to return to Earth quickly. Thinking fast, John simply leaps from the vessel as it enters Earth's atmosphere, using a piece of Prothean sheet metal as a heat shield.

### Return to Earth

After a vicious series of firefights, captures and escapes, 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 camouflaged-Arbiter, believing that the Elites were still a human enemy. Johnson informed him that the two races were now allies, as a result of the Great Schism. The disillusioned Arbiter and the Sangheili species had been expelled from the Covenant and were now working together with the humans.

    John and the Arbiter, along with Johnson 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, who knew of Johnson's strategic value. They were soon rescued by John, 'Vadam and their men. After taking heavy fire from Phantoms, a Pelican dropship evacuated the team to a nearby still-intact 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 Prothean artifact near Voi. Lieutenant Commander Keyes decided to evacuate all troops before Truth could launch his assault. John, Thel, Johnson and the remaining UNSC Marines defended the base during its evacuation. Johnson and the Arbiter would evacuate beforehand, planting a massive bomb to destroy the base along with the invading Covenant forces. However, when the command center was taken by the Covenant, the bomb was deactivated. The Master Chief tore his way through dozens of Jiralhanae warriors, re-activating the bomb and 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 end of the Battle of Voi, John dashed towards what was believed to be the Ark. Instead, the artifact opened a mass-relay-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 in-atmosphere frigates to fire upon Truth's Dreadnought. Unfortunately, MAC rounds had little effect on the Dreadnought's advanced shielding, and Truth fled through the Portal with his remaining loyalist forces. The UNSC remained behind on Earth to determine their next move. Sangheili-led Covenant seperatist forces would arrive on Earth to provide post-disaster aid to the battered planet.

Just as the battle seemed over, a Flood-infested Covenant warship from *High Charity* crash-landed in Voi via an in-atmosphere warpspace jump. John, the Arbiter 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. However, due to seperatist aid, most surviving civilians were able to get to safety.

The Sangheili and the UNSC leaders watched Cortana's recording, which contained a warning that *High Charity*, now overwhelmed by Flood 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, the Arbiter and most of the Covenant seperatist forces 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 UNSC *Forward Unto Dawn* to the Ark*.*

### Installation 00

*Main article: Battle of Installation 00*

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 human infantry strike team descended in Pelicans and Phantoms while the Shipmaster's Sangheili 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 frigate UNSC *Forward Unto Dawn*, 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-117 began to discover a number of terminals containing ancient Prothean communications logs, as well as direct messages from the Prothean ancilla Mendicant Bias.

John-117, Thel 'Vadam, and several squads of Marines and Covenant seperatists 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 and his squad were captured at the third. His entire squad was executed, with Johnson spared only to activate the Halos from the Ark's Citadel. John, 'Vadam, and the Marines and 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* arrived at the Ark, having entered by the Mombasa Portal back at Earth. Their arrival brought the Flood into the conflict and disabled the *Shadow of Intent*, with a direct hit to their hull.

After defeating the last remnants of the Covenant forces around the Citadel, including two Scarabs, Chief 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 by Brutes. 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, the Gravemind using them to achieve his own goals. 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 over the past few months, 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 04B and destroy the Flood once and for all. But first, he headed to the remains of *High Charity* to keep a promise to Cortana.

Once 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 Halo

*Main article: Activation of Installation 04b*
The final mission of the war for John, 'Vadam, and Cortana was to destroy the Flood forever by activating the replacement Installation 04 and destroying the Gravemind, who, thanks to *High Charity'*s timely arrival, was now within reach. John, Thel and Cortana were fully prepared to die on the ring, with the rest of the human and Sanheili forces departing the Ark and returning to Earth. The three landed on the Halo, discovering that the Gravemind 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 with a Spartan Laser, having stayed behind from the rest of the fleet.

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 who destroyed Guilty Spark once and for all with an energy blast to his central sensor. Avery suffered third degree burns and determined that his injury was fatal, and he requested that his friend "send [him] out *with a bang*," after handing over Cortana's data chip. His last words were, *"Don't*ever*let her go."*

Cortana then activated Installation 04B, and she, John and Thel fled to the *Forward Unto Dawn* onboard a Warthog, fighting the Flood and local Sentinels on the way. The team boarded the *Dawn* and escaped the firing and destruction of ring and the Ark. However, the mass relay portal the frigate opened could not sustain itself under the stress, and its closure severed the ship in half, sending 'Vadam's half to Earth. John and Cortana were left drifting in unknown space.

## Missing in action

John and Cortana were presumed dead after several months of searching by ONI's director, Admiral Parangosky. The forward half of the *Forward Unto Dawn*, bearing the Arbiter, crash-landed on Earth. Lord Hood commissioned a memorial near Mount Kilimanjaro in Africa in honor of UNSC service members lost during the war, specifically the Battle of Installation 00. John's Spartan tag was carved onto the memorial by Avery Johnson's family and was accompanied by the insignia of the Master Chief Petty Officer of the Navy.

## Stranded in space

John-117 and Cortana managed to survive the explosion of Installation 04B 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 or even centuries before anyone could discover their distress signal. In a similar conversation to the one they shared 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 her knowledge of 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

*Main article: First Battle of Requiem*

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 Prothean shield world. As Covenant Remnant 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 Remnant forces occupying the structure, John was attacked by advanced Prothean defense drones which Cortana identified as Prometheans. Evading or destroying pursuit, John attempted to warn the approaching UNSC *Infinity* 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 been imprisoned within Requiem. Instead of contacting the *Infinity*, John had accidentally released the Ur-Didact, an ancient Prothean warrior, from his Cryptum. Easily disabling John with his powerful biotic abilities, he declared the return of the Protheans as this cycle's rulers and saviors. Humanity remained weak and unworthy in his eyes of inheriting the Mantle. Having always revered the Protheans as gods, the Covenant Remnant quickly swore alliance to the Didact and his armies.

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, who John had previously met on Circinius IV over thirty years earlier in 2526. 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

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.[60] 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 theComposer. 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.[61]

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 aPelican 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.[62] 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.[63]