Avery Johnson

"Send me out... with a bang."

- Sergeant Johnson's last words.

Sergeant Major Avery Junior Johnson, Service Number 48789-20114-AJ, was an energetic Non-commissioned officer (NCO) in the UNSC Marine Corps and a highly trained marine in NAVSPECWAR. He played a vital role in all three Halo games, providing assistance to John-117 at very opportunistic times. He is one of the select few who are acquainted with the Chief, after the two fought alongside each other numerous times. He also had a strange liking for flip music and rock 'n roll, which wasn't shared amongst his fellow soldiers and subordinates. He was renowned for his never-say-die attitude and was well respected and liked amongst his soldiers. He died during the Battle of Installation 04(II), at the hands of a rampant 343 Guilty Spark when he shrugged off Spark's protests against prematurely firing an incomplete Installation 04. Sgt. Johnson is the only known sentient lifeform not infected by the Flood, other than the Master Chief in Halo: The Flood, after making physical contact with an Infection form (although Johnson is saved because of Boren's Syndrome, whereas the Chief is saved because of Cortana's intervention).

Early Life
Avery Junior Johnson was born in the sprawling industrial section of Chicago, Illinois near the Great Lakes of the United States of America. His family broke up when he was six and he was placed in the care of his Aunt by Zone Protective Services. One event that Johnson had fond memories of was his first day of church, as his Aunt tried her best to get the large shoes and small clothes of his cousins to fit him. Her religious beliefs resonated within Johnson and often made him question his own decision to kill other human beings, even long after her death. But since his hatred towards the Covenant, he does not hesitate when it comes to killing those who support the Covenant.

Early Career in UNSC Marine Corps and NAVSPECWAR
Johnson enlisted in the UNSC Marine Corps when he was nineteen and was soon thrown into the Insurrection. His name was dubiously associated with dozens of black operations and programs, including assignment to the highly classified unit called ORION Project, and participation on missions codenamed Operation: TANGLEWOOD and Operation: KALEIDOSCOPE.

Johnson is speculated of being a Spartan-I and may be a member of Project: SPARTAN-I. The files that contain the records of his involvement with the program are covered up by ONI Section Zero, and anyone who tries to access them are automatically sent a fake file marked "\P_BS48789-2011-AJ.txt", also known as the "Paris/BS Spoof" File. He is an graduate of the Naval Special Warfare Sniper School, and has received training in Human Entry Vehicle orbital drops, and CQB (Close Quarters Battle), while serving in NAVSPECWAR. He also has served as a Squad Leader on many black operations during the Insurrection.

Johnson participated in Operation: TREBUCHET in 2524 leading Alpha Squad of a platoon of NAVSPECWAR marines alongside Staff Sergeant Byrne. Their squads used Hornets to conduct air assaults on multiple targets in efforts to eliminate Rebel bomb making factories. However, when a rebel (armed with a bomb) was cornered in a Jim Dandy restaurant, Byrne told Johnson to fire an M99 Special Application Scoped Rifle, (A.K.A gauss-rifle), at an Insurrectionist holding a child hostage. Johnson did not have a clear shot at the rebel, and his hesitation led to a civilian (a man trying to rescue his son) tackling the female rebel, who then detonated her explosives, which destroyed the Jim Dandy restaurant, along with all of the Marines in Byrne's squad and thirty eight civilians.

After the incident, he found his Aunt dead, and soon went on a massive drinking binge. He started a brawl with bouncers at a Chicago Club, and ended up in a gutter until he was found by a UNSC Marine Corps recruiter. He was re-assigned to Harvest by Jilan al-Cygni.

Battle of Harvest


Officially, he was re-assigned to train the Colonial Militia on Harvest, but their actual mission was to create an covert anti-insurgency unit, and to lay an ambush on insurgent forces suspected in the disappearances of DCS freighters around Harvest. However, He and Byrne fought four Jackals in the first battle between the UNSC and Covenant,on board the human Freighter called This End Up, and they successfully defeated them. Johnson and Byrne (with the rest of the militia of harvest) were also present at the initial negotiations between the Brutes and the Humans. They also fought Tartarus, Maccabeus and several Grunts. He aided Staff Sergeant Byrne and ONI operative Jilan al-Cygni in repelling the Brute ship Rapid Conversion long enough to allow most of the planet's population to escape into the Tiara, a station attached to seven different Space elevators stationed on the planet. Later, he would become intimate with al-Cygni after escaping from the planet. After this, his UNSC career is unknown, but he is presumed to have served on many planets between 2525 and 2549, when the Battle of Paris IV took place.

Paris IV
A query by Cortana into Johnson's medical history revealed the information that he had a condition known as Boren's Syndrome, which enabled him to resist Flood infection. This meant that he was able to survive the Flood when they attacked him, Jacob Keyes and the other members of Fire Team Charlie in a Forerunner lab. This disease was contracted while he was stationed at Paris IV. When the Covenant attacked Paris IV, Sergeant Johnson fought valiantly; during the battle, he repossessed a crate of plasma grenades when his troops needed them and used them all against the enemy troops to keep them at bay so his fellow soldiers could evacuate. He received a commendation for bravery, and a twelve-hundred-rad cumulative dose of radiation as an unanticipated "bonus" from the plasma grenades. However, the Boren’s Syndrome had an unexpected side effect; it made him effectively immune to the Flood because the radiation scrambled his DNA structure so much that the Flood could not force a match. This rendered the Flood unable to control him. However, the Boren’s Syndrome is possibly a fake reason, as to cover up his involvement in the SPARTAN-I Program.

Battle of Reach
Main Article: Battle of Reach

After the Siege of Paris IV, he was assigned to Reach Station Gamma, a military station above the planet Reach. While stationed there, a massive Covenant armada arrived, beginning the Battle of Reach. During the battle, Johnson led a search and destroy team aboard the station, and was almost killed by the attacking Jackals and Elites, but was later picked up by John-117 and Linda-058. He escaped onto the Pillar of Autumn, which fled the battle into Slipspace.

Installation 04
"Men, we led those dumb bugs out to the middle of nowhere to keep 'em from gettin' their filthy claws on Earth. But, we stumbled onto somethin' they're so hot for, that they're scramblin' over each other to get it. Now I don't care if it's God's own anti-son-of-a-bitch machine or a giant hula-hoop; We're not gonna let them have it! What we will let them have is a belly full of lead and a pool of their own blood to drown in!"

- Sergeant Johnson ('Pillar of Autumn' level on Legendary)

Coming out of Slipspace, the Pillar of Autumn came across Installation 04. The Covenant, too scared to damage the ring world by firing at the Autumn in space, began boarding actions to "cleanly" neutralize the Autumn by boarding the ship and wiping out the crew and altering its course away from the Installation, before planting charges and blowing it up. On board, Johnson helped defend the Autumn from the invading Covenant boarding troops, but like everyone else was forced to abandon ship when Captain Jacob Keyes issued the order. Johnson was reported to be one of the last to leave the ship, ensuring that as many of the ship's crew - marines and UNSC Navy personnel - made it off the Autumn as possible.

Johnson’s escape pod and his squad successfully landed on the ring with all of the marines dead. However, as soon as they geared up, the Covenant strike teams viciously attacked them. With his platoon scattered all over the valley, he was glad to see SPARTAN-117 coming up to assist in the nick of time. .

Johnson and Fire Team Charlie were evacuated by Echo 419, and remained at Alpha Base for some time until asked to join a mission led by Captain Keyes.

Escape from the Flood
The crew intercepted a Covenant transmission detailing the transport of numerous weapons to somewhere in the swampy regions of Installation 04. This, as well as a captured Elite's testimony of a large weapons cache located in a swamp, prompted Captain Keyes to investigate. Johnson, being an experienced and respected Marine sergeant, accompanied Captain Keyes along with his squad.

Shortly after they were dropped off, the squads came across a structure leading underground. As they ventured further into the facility, they came across several Elite corpses with scrambled innards. Passing them off as friendly fire, they proceeded deeper into the facility until they entered a seemingly empty room. Annoyed with Private Mendoza’s whining, Johnson passed off the situation until little Infection Forms barged out of the nearby holding cells and attacked the squad. As each marine fell, he was one of the victims of an assimilation attempt into a Combat Form, but the complications caused by his Boren's Syndrome rendered him immune from the Infection Forms. This encounter also seems to have left him with some curious regenerative abilities. Alive and well, Johnson was forced to attack and kill his own Marines, who were mutating before his eyes and would have killed him if he had waited any longer. Johnson fought his way out of the nightmare through sheer tenacity and firepower. He was presumed dead after SPARTAN-117 found a helmet recorder entry from Private Wallace Jenkins, showing the gory details of the Marines' fates, but may have been extracted from the swamp with Private Bisenti and the rest of Corporal Loviks' surviving marines by Echo 419.

Escape from Installation 04
"Hell, Chief, it’ll take more than that pack of walking alien horror-show freaks to take out Sergeant A. J. Johnson."

- Avery J. Johnson

Johnson met up with Lieutenant Elias Haverson, Corporal Locklear, and Sheila Polaski, after escaping the destruction of the ring in a Pelican, moments before it collapsed in multiple explosions. Though in the Legendary Ending of Halo: Combat Evolved, Johnson is seen hugging a Elite as the Pillar of Autumn explodes which made his return in Halo 2 a surprise for many fans of the series who thought he had died.

Polaski piloted the dropship away from the ring, meeting up with a C709 ‘‘Longsword’’-class Starfighter carrying SPARTAN-117 and the AI, Cortana, who had also escaped the Flood and Installation 04. Having seen Jenkins’s video himself, John was alarmed by Johnson’s appearance and promptly pulled Johnson's own M6D Pistol and pointed it to his head. It took Cortana to convince Master Chief that Johnson was not infected.

Without a viable way to return to the nearest safe outpost, it was decided that the new crew would take over the nearest Covenant ship in the vicinity, the ‘‘Ascendant Justice’’. The Master Chief assumed command, although Lieutenant Haverson was the ranking officer, and Johnson backed him up by helping him assert control over Locklear and Haverson. After they boarded the Ascendant Justice, Johnson and the others made their way through the ship towards the bridge, where he witnessed a showdown between SPARTAN-117 and a Sangheili, where he brought down the alien’s shields in order for Spartan-117 to win.

Return to Reach
When they arrived at Reach, it was almost completely glassed, except for a small portion. Using a Covenant dropship, they traveled to the surface of the near-dead planet, where Johnson was becoming nervous. After they landed, they found the surviving Spartans and Dr. Catherine Halsey.

Johnson accompanied the new and growing crew as the ship moved through Slipspace. Unknown to him, Dr. Halsey and the Master Chief were reviewing his medical files. They matched Johnson’s survival with the Flood to his Boren’s Syndrome: Flood DNA was present in Johnson’s blood, but was dormant and non-infectious. Halsey also confirmed that Johnson had gained some unique regenerative abilities as a side affect from the attempted assimilation back on Halo. Halsey had prepared two separate documents for ONI Section Three to review:


 * All relevant data on Halsey’s analysis and the possible technology to counter an initial Flood infestation.


 * The file above, as well as Jenkins’s and Johnson’s mission logs as well as Johnson’s medical files.

Halsey placed the decision of which data crystal to give to ONI in the Chief's hands. If he gave them the second crystal, ONI would have probably dissected Johnson in order to figure out how he resisted the Flood, killing the Sergeant. The Chief later decided to save Johnson's life by crushing the second crystal.

Operation: FIRST STRIKE
"I'm not sure what that thing is. Don't look like any 'uneven elephant' to me—more like two squids kissing."

- Avery J. Johnson

Although Johnson's involvement in Operation: FIRST STRIKE was minimal, he came up with the idea to attack the Covenant ship Unyielding Hierophant in order to delay the Covenant from finding Earth. Johnson continued to be of assistance when the Spartans launched Operation: FIRST STRIKE, staying behind with Cortana in the damaged UNSC Gettysburg while they charged head-on into the Covenant ship after the operation.

First Battle of Earth


"The message just repeats. 'Regret, Regret, Regret.'"

- Cortana "Catchy. Any idea what it means?"

- Commander Keyes "Dear Humanity... we regret being alien bastards. We regret coming to Earth. And we most definitely regret the Corps just blew up our raggedy-ass fleet!"

- Avery J. Johnson

"Hoo-rah!"

- Pelican Pilot and Co-Pilot

Most of the crew returned to Earth safely, and they were given time to rest and were debriefed on their experiences. Aboard the Cairo, Johnson was promoted to Sergeant Major and was awarded the Colonial Cross for his actions on Halo. During the ceremony, a Covenant excavation fleet headed by the Prophet of Regret arrived at Earth, sparking the battle.

Johnson aided the defense of the Cairo along with John-117. As the Spartan led the human forces deeper into the station, Johnson and Commander Miranda Keyes boarded the UNSC Frigate In Amber Clad.

As they arrived on the surface, Cortana intercepted data that pointed towards one of the Covenant’s spiritual leaders. Johnson led the Pelicans into battle, but they were shot down by a Covenant Scarab before they got close to the ship that carried the High Prophet of Regret. Using a SRS99C-S2 AM, Johnson fought in the residential district of the city, providing cover fire and serving as a lookout. As John-117 went on to find ODSTs from another downed Pelican, Johnson stayed back and joined the rescue units to provide cover. Viewing the Scarab as a threat to the mission, he returned to In Amber Clad to bring a Scorpion tank for the Chief to use in a front line assault against the Covenant invasion force. Together, they attacked the giant walker, as Johnson provided supplemental troops to back up SPARTAN-117 in his attack.

After the destruction of the Scarab, Johnson picked up the Chief and brought him back into In Amber Clad, just as the massive Covenant ship took off into Slipspace.

Delta Halo
""It's like a postcard: Dear Sarge, kicking ass in outer space, wish you were here."

- Marine ODST

"I heard that jackass.""

- Avery J. Johnson

Coming out of Slipspace, Johnson was shocked to learn that there was another Halo, nearly choking on his ever-present cigar. Determined to find and capture the Prophet of Regret, Commander Keyes ordered SPARTAN-117 to clear a landing zone and the Sergeant to take two flights of Pelicans and land on the ring. Johnson carried out the orders and and followed SPARTAN-117 and a small detachment of elite Orbital Drop Shock Troopers onto the surface, providing artillery and troops to fight the Covenant stationed in the ring’s ancient temples.

During the mission, Cortana translated a message from Regret being broadcast on the Covenant network: Regret planned to activate Halo. Pulling information gathered from the previous ring visited, Keyes found the location of Delta Halo’s library housing the Index. She ordered Johnson to extract his troops and return to In Amber Clad for reassignment.

Search for the Index
"You know, your father never asked me for help either!"

- Avery J. Johnson, lending a hand to Commander Miranda Keyes

Johnson and a group of his best Marines joined Keyes on a search for the Index. As they neared the center of the massive structure, the small pack was attacked by a large amount of Flood. They dug in and fought the creatures off, finally locating the Index. Johnson helped Miranda grab the key, but before they headed out, they were attacked by the Arbiter, who had activated his camouflage to hide from Johnson and Miranda. Johnson was quickly incapacitated, and was captured by the Brute Chieftain Tartarus.

The Fight to Deactivate Installation 05
"Listen. You don't like me, and I sure as hell don't like you. But if we don't do something, Mr. Mohawk's gonna activate this ring and we're all gonna die."

- Avery J. Johnson to the Arbiter on a Scarab in Halo 2

Johnson and Keyes were held in the Covenant city of High Charity, until the High Prophet of Truth told Tartarus to activate the ring to initiate the Great Journey. Tartarus ordered the Jiralhanae to split Johnson, and Keyes and the captured Oracle into two different Phantoms. Johnson was joined by Sergeant Banks and Sergeant Stacker for an execution by a pack of Jiralhanae. Moments before their deaths, the Arbiter and his squad burst out of the nearby structure and attacked the Jiralhanae, distracting them long enough for Johnson and his Marines to board the nearby Scarab walker.

After the executioners were killed, Johnson and his Marines commandeered the Scarab, and confronted the Arbiter. They both agreed that Tartarus needed to be stopped. Johnson suggested that the Arbiter commandeer a Banshee to provide air support. After that, they joined forces and traveled through the canyon towards the Control Room. Knowing the brute strength of the Scarab's main weapon, Johnson fired at the heavily armored door, shattering it with ease. Arming himself with a Beam Rifle, Johnson followed the Arbiter inside.

"Come on Arbiter! Kick that guy's ass!"

- Avery J. Johnson

"Please... don't shake the light bulb!"

- Avery J. Johnson interrupts Tartarus' rant at 343 Guilty Spark

He arrived during the Arbiter's confrontation to Tartarus. He aimed his Beam Rifle at the Jiralhanae’s head, keeping him from forcing Keyes to insert the Index. Tartarus threw 343 Guilty Spark at Johnson, knocking him over. Quickly, he forced Miranda Keyes to insert the Index into the control panel, starting the firing process. The Arbiter and his squad challenged Tartarus, and Johnson provided backup, using his Beam Rifle to bring down the Chieftain’s shields. With his shields down, the Arbiter was able to kill the Jiralhanae, therefore allowing Miranda to grab the Index and stop Halo from firing. With the remainder of the Sangheili squad keeping the area secure, 343 Guilty Spark explained to Johnson and Keyes that the other Installations were ready to fire. This is a fail-safe if one of the Halo installations misfires, allowing them to be put on standby mode. This allowed them to be fired by the Ark.

Rejoining the Chief
"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..."

- Avery J. Johnson, discovering the Master Chief's reckless departure from the Prophet of Truth's ship



When Spartan-117 crash-landed on Earth, he was met by Johnson, the Arbiter, and a squad of Marines. After a few minutes of hiking through the jungle, he and his squad split off from the Master Chief and the Arbiter after encountering enemy Phantoms, reasoning that they would be safer apart than together. Johnson and his team proceeded to continue through the woods, and arrived at the evacuation site several moments before John-117 and the Arbiter. However, enemy Banshees soon discovered the awaiting Pelicans, and he was shot down, crash landing about a kilometer away. He and the surviving Marines were forced to flee pursuing Brutes. At some point Johnson and his men were captured and tortured. After being freed by John-117, he grabbed the nearest weapon and helped fend off incoming Covenant until Hocus, a Pelican pilot, could come to the rescue. Johnson was evacuated along with John-117, the Arbiter and surviving Marines.

Defending Crows Nest
"Go on, Chief. The Arbiter and I will guard the ops center."

- Avery J. Johnson urges the Chief to the hangar

Sgt. Johnson, John-117 and the Arbiter were brought to a UNSC base codenamed "Crow's Nest", deep underground in the African jungle. There, they linked up with Commander Miranda Keyes, who briefed them on the situation. He and the Arbiter stayed behind to defend the ops centre from Covenant attacks, while John-117 went off to secure the perimeter. After a lengthy battle, he was forced to fall back as Jiralhanae overran the control room. He rendezvoused with Keyes and the Arbiter in a Pelican, and guided John-117 through the base to an elevator that would take him to the Pelicans. Unfortunately, the base exploded before John-117 could reach Johnson, and Johnson was forced to take off.

Battle of Voi
"The Brutes have a tight perimeter, Chief. These Warthogs should help you punch through."

- Avery J. Johnson offering a pair of Warthogs to help the Chief on his way

Johnson warned John-117 that the Covenant had uncovered the Ark, and that John-117 had to get to it. Johnson provided air support for the Spartan and the Marine survivors, dropping off Warthogs so the Chief and Marines could break through the Jiralhanae blockades. At one point, he dropped off a Mongoose ATV to assist the Master Chief in destroying a Covenant Scarab. Johnson remained in a Pelican dropship for most if not all of the Battle of Voi, dispersing armor and troops throughout the city as necessary to help push the Covenant back. When the Pelican made a crash-landing in Voi, Johnson probably docked on the UNSC Forward Unto Dawn along with Commander Keyes. He was present when the Master Chief retrieved Cortana and played back her message, and was one of the Marines that followed The High Prophet of Truth to The Ark

The Ark
"Shall I help you choose a vehicle, Reclaimer? This one seems in very good condition, about the standard. Primitive armor not withstanding."

- 343 Guilty Spark

"A tank's a tank, light bulb."

- Avery J. Johnson

"ETA...Damn Quick."

- Sergeant Johnson pulling in to extract the Master Chief from the Cartographer

Johnson descended to the Ark with a half a dozen Pelicans along with John-117, and helped him secure a landing zone and stop the construction of an AA battery. He later brought in some tanks from the frigate, helping throughout the mission, until the location of Truth was discovered from the Cartographer.

He then went on to command the second squad in taking down the third tower that was projecting the shield barrier protecting Truth in the Citadel. There, he, along with his squad, was overrun and captured by overwhelming Jiralhanae forces.

The Prophet of Truth attempted to use him to activate the Ark, but he only taunted the Jiralhanae, in particular a Chieftain and took their abuse. Miranda attempted to rescue him by crashing a Pelican through a large observatory window, but was surrounded. Realizing what the Prophet of Truth wished to use them for, Johnson told her that she should kill them both so they could not be used. While Miranda hesitated, the Prophet of Truth interrupted them, who shot Miranda in the back with a Spiker, killing her instantly. Johnson was rescued by John-117 and the Arbiter, along with a horde of Flood. After the Flood turned on the three, Johnson managed to escape on Miranda's Pelican, but the Arbiter and Chief where knocked off of the Pelican by the Gravemind, forced to fight back through the Flood.

Halo
"Don't let her go, Chief....Don't..Ever...let her go."

- Avery J. Johnson in his last moments , said to John-117

Johnson helped John-117 fight through hordes of Flood to get to the control room of the newly rebuilt Installation 04, giving cover fire for the Chief and Arbiter with a Spartan Laser. Johnson tried to activate the ring despite Guilty Spark's suggestion that they wait for it to be finished, which could take several days. Driven rampant by his own intuition that the ring "Belonged to him". Spark fired his main beam weapon at Johnson, burning a hole in his chest, causing a fatal wound.

While John-117 fought the rogue construct, Johnson used his Laser to damage Spark, and told the Master Chief to "Kick his ass" while he handed John-117 his weapon and afterward lost consciousness. After Spark was destroyed, he gave John-117 the chip containing Cortana, and told him to "never let her go". Despite John's promise that they would not leave him behind, Johnson knew that he wasn't going to make it, John tried to get him out and Johnson told the Chief to 'send him out with a bang'. Following his wishes John-117 left his body in the control room as the premature ring activated and tore itself apart. Johnson's body, after the activation, fell into a large chasm.

Appearances

 * Halo: Combat Evolved
 * Halo 2
 * Halo 3
 * Halo: The Fall of Reach
 * Halo: The Flood
 * Halo: First Strike
 * Halo: Contact Harvest
 * Halo: Graphic Novel

Battles

 * Insurrection
 * Operation: KALEIDOSCOPE
 * Operation: TANGLEWOOD
 * Operation: TREBUCHET
 * Human-Covenant War
 * First Battle of Harvest
 * Siege of Paris IV
 * Battle of Reach
 * Battle of Installation 04
 * Operation: First Strike
 * First Battle of Earth
 * Battle of New Mombasa
 * Battle of Installation 05
 * Second Battle of Earth
 * Battle of Voi
 * Battle of Installation 00
 * Battle of Installation 04 (II)

Medals
Johnson has received three known medals in his service: The Medal of Honor, the Colonial-Cross and the Purple Heart. Johnson was not awarded any medals during his time with the ORION detachment, due to the sensitive nature of it's missions.

Dreams
Avery Johnson was known to have "chronic" nightmares, usually about his last mission. Some of his dreams include the bombing of the Jim Dandy, and his sniping of a suspected Insurrectionist bomber, who turned out to be a normal civilian who picked up the wrong load. They usually plague him during cryo sleep during the thaw phase.

Personality
Avery Johnson's behavior seems to be eccentric, often delivering outlandish speeches to boost the morale of those serving under him. However, as shown in Contact Harvest, he was a no-nonsense NCO, who, although caring deeply for his troops, pushed them hard in training.

Another peculiar aspect of his behavior is that he never refers to John-117 or any of the other SPARTAN-IIs as "Section Three freaks" or "Inhuman cyborgs". He has a large amount of respect for them, and appears to respect every human fighting for humanity, as well as the Elites, once they join forces with the UNSC in Halo 3.

In Halo 1 and 2, Johnson seemed energetic and well humored, often cracking jokes, puns, and insults at the expense of the Covenant or even in response to UNSC transmissions

"Dear Humanity, we regret being alien bastards, we regret coming to Earth, and we most definitely regret that the Corps just blew up our raggedy-ass fleet!"

- In response to Miranda Keyes at the beginning of the Halo 2 campaign level, Outskirts.

However, in Halo 3 it appears that Johnson's age begins to catch up with him, as he is captured (and saved, rather than escaping) numerous times, has fewer humorous lines, and generally appears to be tired. This may be due to old age, his encounters with the Flood, or the Human-Covenant War finally taking its toll on him.

Trivia

 * Johnson engages in notably less combat after Halo: CE, in which he could appear in 5 levels. In Halo 2, he appears in only 3 levels. In Halo 3, his combat role (that the player sees) is the smallest yet, he only fights in Sierra 117, a very brief time in Crow's Nest, and Halo. He appears on the gun of Kilo 23 in The Ark, and appears in the cut scenes for several other missions, as well as sending COM transmissions.
 * In the Halo game trilogy, The Master Chief first encounters Johnson on the level Halo in Halo: Combat Evolved. He last encounters him on Halo in Halo 3.
 * Avery Johnson has Boren's Syndrome, making him immune to Flood infection. However, if one kills Johnson on Halo and then quickly skips to the cutscene, he will still be alive. He then has the stamina of a regular Marine--one Infection Form is able to kill, and then infect him. He will sometimes, with the IWHBYD skull on, say something like, "Ain't I supposed to be immune to this?"
 * Avery Johnson is invincible in Halo 2, and is immune to anything other than a headshot or taking direct hits from several clips from weapons in Halo 3. And in Halo: CE, if you kill him, he will still appear in later levels. This is due to the random generation of bipeds in the game for Marines.
 * He was the first soldier to fight and kill a member of the Covenant, and therefore the first human being to take the life of an alien.
 * Although Johnson is usually labelled as a sniper, he is only seen using a sniper rifle on the levels Assault on the Control Room (Halo: CE)and Outskirts (Halo 2), and a Beam Rifle in The Great Journey, the Graphic Novel and the first chapter of Contact Harvest. In all of his other appearances, he is either wielding an MA5B Assault Rifle, a BR55 Battle Rifle, a Spartan Laser, or a Pistol.
 * In Halo 2, you can see weary bags under Johnson's eyes, as if his encounter with the Flood on Installation 04 had scarred him.
 * In Halo 3, Johnson's skin tone has lightened considerably.
 * Johnson resembles the attitude of Augustus "Cole Train" Cole from Gears of War.
 * In Halo: Combat Evolved, the popular Elite quote "Wort, wort, wort!" is actually a slower reversal of Johnson saying, "Go, go, go!"
 * It may be presumed that Johnson could be or was married according to a quote during gameplay on the level Cairo Station where Johnson himself says that the Covenant are worse than his mother-in-law. However, this could just be a joke.
 * In Halo: Contact Harvest Johnson was involved in a romantic relationship with his Commanding Officer, Jilan al-Cygni.
 * In Halo: Combat Evolved, Halo: The Flood, and Halo: First Strike, Johnson is shown to enjoy flip music.
 * In Halo: Contact Harvest, Johnson's call sign is Crawler.
 * Johnson prefers Sweet William Cigars, like Senior-CPO Franklin Mendez.
 * Johnson made a reference to Captain Keyes in the level "Truth and Reconciliation" when he took a Needler in Sierra 117.
 * The character of Sergeant Johnson first appeared in a short video shown to kick off the Halo Launch Party held in Chicago on November 10, 2001.
 * His voice is portrayed by David Scully in the games, who also voices a number of Elites as well.
 * Sergeant Johnson would appear to be partially based on the character "Gunnery Sergeant Al Apone" from the film Aliens, with whom Johnson shares many character and physical traits, as well as some dialogue.
 * It has been suggested that he is a SPARTAN-I. In Halo: Contact Harvest, Johnson awakes from Cryo despite three times the normal amount of drugs.
 * In an outtake for Halo 2, David Scully says, "They told me that in Halo 4, I get a woman".
 * Johnson is the only Human (in Halo 2) to call the Arbiter by his name.
 * Johnson, Reynolds, and Stacker all have a bulletproof hat in Halo 2, and Halo 3. If you shoot it with a weapon like a pistol the rounds will spark off it. This could be a a game glitch or it could be a regulatory UNSC Sergeant hat.
 * In Halo: CE, on the first level Johnson can be seen having an identical clone in combat and you can sometimes find him dead all over the ship even though he was just in the room you helped him and the marines clear.