Catherine Halsey

This article is about the creator of the SPARTAN Program. For the SPARTAN-III, see Catherine-B320.

Template:Character Infobox

"Spartans never die? If only that were true."

— Catherine Halsey

Catherine Elizabeth Halsey, MD, PhD, (Civilian Consultant 409871) is a controversial but highly praised scientist and an employee of the Office of Naval Intelligence, best known for her work with the SPARTAN-II Program and for overseeing the development of the MJOLNIR Powered Assault Armor. Despite being a civilian, she held considerable authority within ONI and commanded considerable respect from many military figures. Publicly, she was well regarded, in particular due to the high esteem she felt for her SPARTANs and for the guilt she endured from condemning them to the life of a super soldier. Dr. Halsey is often referred to by the name "Charlie Hotel", which is her initials in phonetic alphabet.

Biography

Early life and career

A self portrait of Halsey, aged eighteen.

Catherine Elizabeth Halsey was born on the colony world Endymion, in the city of Port Vernon, on March 19th, 2492. Not much is known about her early life, but what little is known gives a glimpse of what would be a promising career. In her own words, she was "...smarter than her parents, always reading, talking, learning, and eager to share her knowledge with anyone who would listen." By 2507, at the age of 15, Dr. Halsey was already writing her second Doctoral Thesis paper, in which she discussed archaic line commands. She was Vice Admiral Ysionris Jeromi's star pupil as well.

In 2507, Halsey met Dr. Elias Carver at an academic social mixer, during which Carver was discussing "the matrix mechanics of the socio-and politico-economic vectors of human expansion". Halsey saw Carver's ideas as genius but his algorithm implementation as obsolete. Carver had used only seven dimensional parameters in his calculations; Halsey thought he needed sixteen and attempted to correct him. Carver did not appreciate being challenged by a young upstart. Halsey later noted that had she known that Carver would commit suicide two years later, she would have been more charitable. However, the future Vice Admiral Michael Stanforth, then a Captain, took note of Halsey. This was the start of Stanforth's continuous aiding of Dr. Halsey with her projects as her military counterpart and protecting her and her projects from those that wanted to see it disbanded in the coming decades.

Three weeks after the occasion, the UNSC approved Halsey's grant proposal for artificial intelligence control for N-dimensional matrices, under the provision that she first successfully test a model of their choosing. It was by testing this model, using both Carver's and her own dimensional parameters, that Halsey was convinced to join the UNSC and work to end the Insurrection. It is also known that at some time in her early life, she supervised the creation of the template for third-generation smart AIs.

In August 2510, Halsey purchased a small, hardback journal in a shop on Reach, near the base she was stationed in. Halsey used the journal as a medium through which to express her thoughts and concerns, as well as important research notes, and would do so for another forty-two years, until she abandoned it during her escape from Sword Base. The journal was later recovered by ONI in 2553, and was designated top secret.

Dr. Halsey served as a scientific adviser for to the Office of Naval Intelligence from 2515 to 2522, when she was made chief scientist. She made huge contributions to many ONI Section III projects, including the creation and deployment of AI constructs. She also created and initiated the SPARTAN-II project as well as the development of the MJOLNIR armor system. These all proved to be important developments for the UNSC, and to the continued survival of mankind. During her service with ONI, Halsey was stationed primarily on the planet Reach. By 2551, she lived in the community of Csongrád.

During their survey travels for the Spartan-II candidates, Halsey grew attached to Jacob Keyes. In November 2524 the two were reunited while attending a conference at the University of Calippus, and the two conceived a child. In 2525, Halsey gave birth to Miranda and raised her for a few years, when on July 12, 2531, Miranda's father agreed to take her in, raising her on Luna. Halsey would later have a falling-out with Miranda, who would later change her legal name to her father's and refuse to speak to Halsey for several years.

SPARTAN-II Program

Main article: SPARTAN-II Program

"This boy could be more useful to the UNSC than a fleet of destroyers, a thousand Junior Grade Lieutenants -- or even me. In the end, the child may be the only thing that makes any difference."

— Catherine Halsey speaking to Lt. Jr. Grade Jacob Keyes, referring to John-117 in Elysium City.

Halsey overlooking Daisy-023's Spartan augmentations.

Halsey began her work on the SPARTAN and MJOLNIR programs in 2511, improving upon the shortcomings of the ORION project. In 2517, at the age of 25, built a set of rigorous genetic requirements that any potential candidate of the program was required to meet. From these requirements, she identified 150 candidates, but ONI would only give her enough funding to train 75 of them. Time constraints made it impossible for her to personally screen every candidate from the Outer Colonies, so she delegated much of the responsibility to her team, while she processed candidates in Sector 4. Junior Lieutenant Jacob Keyes accompanied her as an attaché during the majority of these interviews, including most notably that of John-117. Halsey then had the children secretly brought to the planet Reach for training. The 'recruited' children were replaced with flash clones, which die at a certain time, due to various neurological and physiological diseases.

With the assistance of Chief Petty Officer Franklin Mendez and the AI Déjà, she proceeded to train the Spartans. She supervised their augmentation procedures, combat training, and education, and studied the effects of the Spartan lifestyle on the children. She kept in close contact with them all throughout their lifetimes, from her base under Reach. Annoyingly, she was always able to tell them apart from each other, even under half a ton of MJOLNIR battle armor. Dr. Halsey always used their first names, never their ranks or Spartan tags. This revealed that she had a huge amount of respect for, and from, the Spartans; she was also able to order them around and the Spartans referred to her as "Ma'am", which is another example of how they respect her, not to mention that they also regard her as a sort of a mother figure. She also knew many of the Spartans' closely held secrets, having taught many to them as children, such as the Oly Oly Oxen Free security tune.

Involvement during Human-Covenant War

Battle of Harvest

Main article: First Battle of Harvest

After first contact with the Covenant, Dr. Halsey accessed LCDR al-Cygni's ONI Sloop Walk of Shame's data archive. During Dr. Halsey's investigation, she began researching the last conversations of the AI Mack, and his choice of misspelled Shakespeare during his last days of rampancy.

Next class of SPARTANs

Despite ONI's intentions to continue with the SPARTAN-II program, Dr. Halsey began having difficulty finding a suitably large number of candidates that fit her genetic and age profiles. Additionally, most of her budget was now being used to maintain the MJOLNIR armor in service. Eventually, ONI discontinued the SPARTAN-II program, reassigned most of its personnel to other projects (such as the SPARTAN-III Program), and buried Halsey in CASTLE Base, cutting off her access to classified material. However, in just a few short years, her SPARTANs would prove themselves to be the most effective weapon the UNSC had against the Covenant. ONI's reticence vanished, her budget mushroomed overnight, and she was offered a corner office in Olympic Tower in New Alexandria. However, Halsey decided to remain in CASTLE as a means of revenge against ONI, which would now have to spend half the day going through security checks.

Capture

Main article: Raid on the Third Fleet of Glorious Consequence

Catherine and John-117 face Thel 'Lodamee on a Covenant assault carrier, Resplendent Fervor

In 2544, Halsey was captured by the Covenant's Third Fleet of Glorious Consequence during the Battle of Miridem, while she was cryonically frozen. A team of SPARTAN-IIs, consisting of John-117, Kelly-087, Frederic-104, Solomon-069, and Arthur-079 were sent to rescue her with OFA92/EVA "Booster Frame" vehicles. Knowing Halsey's value to both the UNSC and the Covenant, Fleet Master Luro 'Taralumee planted decoys in several of the fleet's CCS-class battlecruisers.

Solomon was killed by one of these decoys, which was actually an antimatter charge giving off a false signal. Arthur was also killed, crushed between two cruisers while covering Kelly-087 from multiple pursuing Seraph fighters. After finding the ship Halsey was on, John, Kelly and Fred fought through large numbers of Covenant forces, though Fred and Kelly were separated during the fight. John soon reached Halsey and rescued her from a cryo pod, but the two were immediately stopped by Major Thel 'Lodamee. Halsey watched as John engaged the Elite in an energy sword duel. However, Fleet Master 'Taralumee detached the section of the ship they were in, retrieving Thel mid-fight via gravity lift, and jumped into Slipspace.

Halsey and John entered an escape pod but were engaged by Seraph fighters. They were soon rescued by Fred and Kelly, who had captured a Seraph fighter. The surviving humans were then recovered by the stealth ship that had deployed the Spartans. Aboard the stealth ship, Halsey comforted John as he swore not to lose another Spartan.

Private projects

Over the course of the war, Halsey worked with her AIs experimenting on new ways to extend the life of smart AI and expand their processing capabilities. She also experimented on her private smart AI "triumvirate", where three AI constructs, arranged in parallel, could divide their algorithms and would decide matters by majority vote. Coincidentally, a similar arrangement was already in use by the Assembly, a group of AIs that kept its existence hidden from humans. In 2547, after thoroughly researching the subject, she stole the decommissioned Slipspace drive of the UNSC Tripping Light, and conducted an experiment on building an abstract fractal in the volume of Slipstream space, in an attempt to create a virtually infinite processing matrix for AIs to inhabit. Though the test was ultimately a failure, the Assembly saw the potential in the concept of residing permanently in the alternate space-time.

Work in SWORD Base

Main article: Fall of Reach

Dr. Halsey finally meeting a Spartan-III.

During the opening stages of the Fall of Reach on July 26, 2552, Halsey was working on an excavation of a underground Forerunner facility beneath ONI's SWORD Base, when the facility came under attack by a Covenant corvette. After the destruction of the corvette, she called NOBLE Team to her laboratory for debriefing, where she learned of the death of her subordinate, Laszlo Sorvad, stabbed through the abdomen by an Elite survey team. After arguing with Carter-A259 over Noble's failure to apprehend the Elites' leader and Catherine-B320's attempted access of restricted files, she learned of the nature of Sorvad's "latchkey" discovery, a way to decipher data found in the Forerunner complex beneath Sword Base. After dismissing Noble Team, she began the decryption process of the "Latchkey" data in the Forerunner complex.

On August 3, Halsey split up Cortana, assigning her "copy" to work on the decryption of the Forerunner data in the underground facility below Sword Base, while her other half would prepare for the Spartans' mission; Operation: RED FLAG. When the UNSC Iroquois arrived at Reach from Sigma Octanus on August 12, Halsey visited the ship. During her visit, Captain Keyes came to see her, and they discussed their daughter Miranda, the Keyes Loop, the Spartans and Operation RED FLAG. Later in the day, she visited Camp Hathcock to see John-117 after his debriefing. On August 27, she met most of the remaining Spartan-IIs at the FLEETCOM military complex in the briefing for RED FLAG.

Halsey hands Cortana's fragment to SPARTAN-B312.

Later, Noble returned after receiving orders to destroy Sword Base. Halsey once again called Noble Team to her, revealing Noble's true orders to them: to transport a package containing "mankind's best chance for survival" to the Halcyon-Class Cruiser Pillar of Autumn, holding position in the Aszod ship breaking yards. After Noble's successful defense of her lab while she prepared the package, she entrusted SPARTAN-B312 with the package: a fragment of the AI Cortana, now uploaded with the information from the Forerunner facility. Once she made certain that Noble Six would deliver Cortana to the Autumn, she left for CASTLE Base under the escort of Jun-A226 while the remaining Noble Team members delivered package to the Autumn.

Refuge under CASTLE Base

After arriving at ONI's CASTLE Base, Halsey volunteered to remain behind to ensure that all UNSC technology was secured from possible capture. She initiated Operation: WHITE GLOVE, destroying several AIs (including Cortana's "older sister" Kalmiya) to keep the Covenant from accessing UNSC databases. With expectations that the Covenant would glass the planet and knowledge that even if they didn't, she would be facing an entire army of Covenant ground forces, it was clearly an offer of sacrifice.

However, this changed when Spartans Fred-104, Kelly-087, Vinh-030, Isaac-039, and Will-043 appeared at the entrance to CASTLE Base. With the firepower to potentially fight their way out, the possibility of surviving CASTLE Base's destruction became available. She gave emergency aid to the Spartans for their injuries, but a data anomaly detected by her accompanying AI, Kalmiya, attracted Dr. Halsey's attention.

The data had been accessed by Araqiel, an AI that worked for Colonel Ackerson, one of Dr. Halsey's main competitors within ONI. After tracing the data access, Dr. Halsey stumbled across the AI, left behind by its master. Araqiel then proceeded to threaten her (he went as far as telling her he would fill the room with poison, and that she would be reported). She started typing in "archaic line commands" to access his code directory and personal fail-safe. She then shut him down. After shutting it down, she proceeded to read through Ackerson's files and discovered a number of things including the location of Onyx, evidence of the SPARTAN-III Program and a map of the mining tunnels CASTLE base had been built upon. The latter particularly interested the Doctor as the file had been classified at X-Ray level, making the file abnormally important for ancient maps. From this, she deduced that there was something of importance under the mountain.

Assuming that at the very least these maps provided a backdoor, she chose to move the Spartans out of the base and into the mineshafts. She then triggered CASTLE Base's self-destruct mechanism and activated the fail-safe on Kalmiya. With the Spartans in tow, they moved into the mineshafts.

Over the course of the next five days, the Spartans and Dr Halsey searched the mines, looking for either an exit or what Dr. Halsey would dub "the most important discovery of the millennium". On the fifth day, Fred discovered an entrance into a large Forerunner structure, and within, the Forerunner crystal. However, the acquiring of the crystal sent a spike of neutrino radiation, attracting the attention of the Covenant. Their location was now threatened by Covenant forces.

Following a Covenant attack, Halsey and her team retreated into a hallway and sealed off the entrance, losing contact with Isaac and Vinh in the process. However, they quickly discovered that the hallway was a dead end. It is presumed that Halsey and the surviving Spartans remained stranded at this location for some time.

Escape from Reach

Days later, a group of Spartans, including John-117, rescued Dr. Halsey and the remaining Spartans and evacuated them from Reach to the captured Ascendant Justice.

Dr. Halsey later saw the importance of destroying this artifact after it caused a Slipspace anomaly that nearly resulted in the destruction of the Ascendant Justice. After escaping Reach, the group fled to Eridanus Secundus in the Eridanus system's asteroid belt, where the Spartan's first mission had been in. While there, she stole the rebel governor's spacecraft and, along with Kelly-087, whom she had sedated, escaped into Slipspace. When asked by Admiral Whitcomb as to the reasons for her actions, she gave a simple UNSC code Three-Nine-Two, which meant that she was on a high priority mission. She entrusted the Forerunner crystal to Corporal Locklear, telling him to keep it safe, hidden, and to do whatever it took to keep it from falling into enemy hands, otherwise the Covenant would be able to go a hundred times faster in Slipspace. The Corporal destroyed the crystal, which is not totally against her orders, and died as a result of the explosion created by the destruction of the Forerunner crystal. The Covenant later recovered a few fragments.

Dr. Halsey's ONI memorial plaque.

In the aftermath of the battle, she was presumed dead by the Office of Naval Intelligence and honored, with other personnel, on a plaque at ONI Alpha Site. It can be assumed the SPARTANs and Johnson neglected to report her retrieval from CASTLE Base then her following kidnap of Kelly and apparent desertion from the UNSC. Another possibility is that her name was added to the wall after the Battle of Reach but before the Spartans returned to Earth. It could also be that the ONI did not want anyone to know that she had kidnapped Kelly, so they covered the incident up by saying she had died.

Battle of Onyx

Main article: Battle of Onyx

Dr. Halsey and Kelly eventually arrived at Onyx, while reuniting with SCPO Mendez and eventually her remaining SPARTAN-II's and the SPARTAN-III's. She helped decipher the mystery of the planet. At first, she tried to maintain secrecy about her intentions out of habit, until Kurt-051 confronted her about it. She admitted that she was not actually looking for Forerunner technology or weapons, but rather the secret Forerunner shield world, which she believed to be equivalent to a bomb shelter, and would be capable of keeping the remaining Spartans safe to evade all current war and let them live to fight another day. Her relative expertise with Forerunner technology was vital to the survival of the UNSC forces on the planet, as she was able to interpret Forerunner glyphs when navigating the facility, guiding the Spartans to the facility's map room, as well as allowing them to quickly move across the megastructure by using its teleportation grid.

At the end of the battle, she, along with Mendez, Blue Team, and the Spartan-III survivors, retreated inside the shield world known the the Forerunners as "the Sharpened Shield", which she correctly deduced to be a "micro" Dyson Sphere, enclosed outside normal space-time within a slipspace bubble.

Post-war

Dr. Halsey and the surviving SPARTANs were eventually rescued from the Sharpened Shield, but Halsey was immediately arrested by Captain Serin Osman for "committing acts likely to aid the enemy". She hijacked a ship, kidnapped a Spartan, and lied to Lord Hood to have him sent more Spartans to Onyx - all with the sole intention of hiding in the shield world until the war was over. Admiral Margaret Parangosky detained Dr. Halsey on the newly-established Ivanoff Station, in orbit around Installation 03, as retaliation for Halsey lying to her and ONI about the use of flash clones at the onset of the SPARTAN-II Program. As far as the public is concerned, Halsey was killed during the Fall of Reach until Parangosky decides otherwise.

At some point after the war, she is heard giving a eulogy for SPARTAN-B312.

Personality

Little is given in the terms of social activities or even a list of friends. Though she had distanced herself from most of her friends from her youth, she would often browse through casualty lists within the UNSC subnet, finding the majority of them dead by the final years of the war. Eventually, she considered her AIs the closest friends she had. Her intelligence is unquestionable as well as the loyalty and respect she receives from the majority of her comrades and her Spartans. However, as seen in Halo: First Strike her judgment is not always correct, although bearing the guilt of the Spartan program, her sense of right and wrong has differed greatly. It is obvious that she truly cares about her Spartans. She has a notable fondness for classical music, especially Debussy, and often asks nearby AIs to play select pieces as she works.

What can be gleaned is that she preferred the company of AIs, and although she may be angered easily at being mentally defeated, always appreciates the simplicity of them. None more than Cortana, who was actually created from a flash clone of her own brain. She is an atheist, lacking belief in the existence of any god.

This section needs expansion. You can help Halopedia by expanding it.

Guilt

Dr. Halsey carried extraordinary guilt because of the SPARTAN-II project, in the feeling that she had exploited the children and destroyed their lives, which was later passed to Cortana. Though she continued to support them and gained monumental prestige for her efforts, she also felt responsible for each one who died. She never could quite justify their exploitation as a "necessary sacrifice." She also had considerable respect for the Spartans, and addressed them by their first names (even with their armor on), which seemed to greatly annoy them.

Her feelings of guilt were made evident by the fact that she often referred mentally to "sacrificing the few to save the many," though this rarely worked to soothe her conscience. By the time she was rescued from Reach by the Ascendant Justice, she simply wanted to save as many lives as she could, believing that the war was not one that the UNSC could possibly win. While she knew that her own Spartans, the SPARTAN-IIs, couldn't be persuaded to turn from the war, she believed the SPARTAN-IIIs may not yet have been fully determined to win the war, and she set out to try and weaken their resolve to fight.

John-117

Halsey also had somewhat of a unique relationship with John-117. Some of this may stem from him being the first subject she observed, but she had a great fondness for him and he was her favorite Spartan. Halsey told Cortana she considers him the luckiest and best of the Spartans and also apparently finds him attractive given her reaction to Cortana's comments on that. Halsey was responsible for John's first promotion to Squad Leader as a result of her acknowledging his leadership skills and suggesting it to Mendez. Halsey also had John's full trust and he always did his best to never undermine her authority.

Halsey decided to test her favorite Spartan's sense of ethics by handing over data concerning Avery Johnson and how his Boren's Syndrome made him immune to the Flood. She knew that if the data was handed over to ONI, Johnson would likely be killed and dissected in order to find a cure to the Flood infection. She estimated that there is a billion to one shot that they could have replicated Johnson's condition, but conversely ONI would do it to save Humanity from a greater foe. At first, John chose to sacrifice Johnson in order to try and save millions of people out of his duty to protect all of Humanity. However, John reconsidered and eventually destroyed the data due in part to the sacrifice of Vice Admiral Danforth Whitcomb and Lieutenant Elias Haverson.

Trivia

• Halsey is voiced by Jen Taylor in Halo: Reach, who also voices Cortana, reinforcing the connection between the two characters. This is also the case in Halo Legends, where Shelley Calene-Black voices both Halsey and Cortana.
• In Halo: First Strike, it is stated that Dr. Halsey was not keen on losing, as seen when she kept losing at a game of Twenty Questions with her training SPARTANs and soon quit playing.
• She had a knack for embarrassing the SPARTANs with the way she was able to tell them apart through subtle habits in their postures, despite their identical MJOLNIR armor, something no other non-SPARTAN was able to do. Unlike most others, Halsey never referred to the SPARTANs by their numerical designations, but by their names. However, she referred to Daisy-023 as "Twenty-Three" when trying to convince Daisy to return to the program.
• She had a bad habit of keeping a messy office and drinking cold coffee, tending to prepare the drink and then become distracted by work, only remembering it hours, sometimes days, later. She preferred darker coffees than those grown on Reach. On January 9, 2535 she met with Chief Petty Officer J. G. Jimes in order to procure quality Beniese coffee.
• Halsey served as a mentor to Professor Ellen Anders at some point prior to 2531, though they apparently had a major falling out, as noted by Anders in the manual, saying "Why mention Halsey here? She hated me and I hated her."
• After the Fall of Reach, she was presumed dead by the Office of Naval Intelligence, although no body was found. She was mentioned in a memorial plaque inside the ONI Alpha Site on Earth. This is odd, considering that John-117, Will-043, Linda-058, Fred-104, Cortana, and Avery Johnson knew she had fled with Kelly-087. However, it is possible that the memorial plaque in question was erected before this news reached Earth.
• Two of Dr. Halsey's statements in The Package are references to similar statements made in the first two Halo games. She tells John-117 that she slept well "No thanks to their driving," which is echoed in Halo: Combat Evolved when he tells Cortana he slept well no thanks to her driving. She also tells John, "Don't make a girl a promise...if you know you can't keep it," which Cortana would tell him in Halo 2.
• Halsey's appearance changes drastically from The Package to Homecoming. In The Package, at which point she is aged fifty-two, she is inexplicably depicted as a fairly young woman with short, blond hair and no glasses. This may or may not have been reflected in the later appearance of Cortana, who was created from the replicated neural pathways of Dr. Halsey herself. Her appearance in Homecoming however, is closer to her description from the books. It should be noted that various concepts in The Package, and Halo Legends in general, result from artistic license. Her appearance in Halo: Reach is much more in line with the description she received in the novels, with the exception of a lack of glasses. In the developer commentary for Homecoming Frank O'Connor states "People tend to think of her as older than she's portrayed... and part of that was simply, you know, it's anime, and they want everyone to be attractive and young. I mean, that's one of the hallmarks anime... I think that IG took the safer of the two routes and sort of disguised her appearance and disguised her age by having it literally obscured by her hair and her glasses and to a certain extent her uniform." In The Package commentary he explains, "She was definitely one of those back-and-forth conversations [with Casio Entertainment]; 'Can you make her older? Can you make her older?' And eventually we got to this compromise... I think if we were casting a real-life actress we'd cast someone a lot older, but in anime the context is fine and it works.'"
• Catherine Halsey is also a character in the novel The Fountainhead. In the novel, Halsey progresses into becoming an altruist, thinking of nothing other than the greater good of the majority. In this sense, she is an opposite of the Halsey of the Halo universe; Dr. Halsey begins by sacrificing the Spartans to buy the UNSC more time, but then changes her mind and does everything she can to save the Spartans, regardless of what happens to the rest of humanity.
• Dr. Halsey's personal journal is included in Halo: Reach's Limited and Legendary Editions. The journal was mostly written by Eric Nylund in conjunction with Bungie and 343 Industries, with Lorraine McLees serving as art director.
• The Assembly has speculated that Halsey's ruthlessness may have been the result of a chemical imbalance.
• Halsey's outfit worn in The Package can be purchased for one's Xbox LIVE avatar for a price of 240 Microsoft Points.
• The barcode on her badge reads HALSEY when scanned with a barcode reader.

Gallery

• Ih halsey portraitb.jpg

  A concept portrait of Halsey for Halo: Reach.

• Ih halsey01.jpg

  Various early iterations of Halsey's outfit in Halo: Reach.

• 

  Halsey facing Cortana, her literal brainchild.

• 

  Dr. Halsey's ONI security badge.

• 

  Dr. Halsey's signature.

• 

  A young Halsey, as depicted in Halo: Fall of Reach.

• The Covenant - Halsey.jpg

  Another image of Halsey in Fall of Reach.

• 

  A render of Catherine Elizabeth Halsey in The Package.

• 

  Halsey as she appears in The Package.

• 

  Halsey in cryostasis.

• HalseyPod 2.jpg

  Halsey being helped out of her cryo pod by John-117.

• HalseyJohn.jpg

  Halsey watches as John is challenged to an energy sword duel by Thel 'Lodamee.

• 

  Halsey as she appears in Homecoming.

• 

  Halsey facing Daisy-023, who has taken several SPARTAN trainers hostage.

• 

  Halsey in an AV-14 Hornet, informing Daisy-023 about the purpose of her flash-clone.

• 

  One of Jacob Keyes' final memories of Halsey before he is assimilated into the Proto-Gravemind.

• 

  Another one of Keyes' memories of her before he is assimilated within the Proto-Gravemind. She is seen shaking his hand.

List of appearances

• Halo 3 (Indirect mention only)
• Halo 3: ODST (Mentioned only)
• Halo: Reach
• Halo: Combat Evolved Anniversary
• Halo: The Fall of Reach (First appearance)
• Halo: The Flood (Mentioned only)
• Halo: First Strike
• Halo: Ghosts of Onyx
• Halo: Contact Harvest (As "Charlie Hotel")
• Halo: The Cole Protocol
• Halo: Evolutions - Essential Tales of the Halo Universe
  • Pariah
  • Human Weakness (Mentioned only)
• Halo: Glasslands
• Halo Legends
  • The Babysitter (Mentioned only)
  • Homecoming
  • The Package
• Halo Graphic Novel
  • Page 122 (Mentioned only)
• Halo Wars: Genesis (Mentioned only)
• Halo: Fall of Reach