Sarah Palmer (Halo)

Spartan Commander Sarah E.[6] Palmer (service number 65287-98303-SP) is a soldier in the Spartan branch of the UNSC Armed Forces and a veteran of the Human-Covenant War. After the war, Palmer transferred from the UNSC Marine Corps Shock Troopers[3] to the newly-independent branch, and was augmented as one of the first SPARTAN-IV supersoldiers.[7] She is currently assigned as the Commanding Officer of the 300-member Spartan contingent aboard UNSC Infinity.[2][4]

Early life and military career
Palmer was born April 13, 2527 on Luna to embittered colonial parents, who possessed a strong dislike of the United Nations Space Command. They died when she was young, however, and she was adopted. Her adopted father did not share the views of her birth parents, and he was instrumental in her joining the UNSC Marine Corps.[8] Palmer joined the Corps sometime during the 2540s, and served twelve tours on eight different worlds as an Orbital Drop Shock Trooper.[2][note 1][note 2]

In 2546, Lance Corporal Palmer was attached to ODST squadron Gamma-Six, under the command of Sergeant Pham during the Covenant's attack on Sargasso. During the battle, the squad was sent to the town of Belisk to protect Lethbridge Industrial's latest military-grade munitions manufactured for the Office of Naval Intelligence. While Gamma-Six protected the facility, ONI tasked Alpha-Nine with retrieval of the facility's research data before the Covenant could claim it.[9] However, Palmer and Gamma-Six were unaware of the fact that ONI had intended for the squad to serve as a distraction, allowing Alpha-Nine to recover the data with little resistance. As Alpha-Nine completed their mission and prepared to leave Belisk, Edward Buck, squad leader for Alpha-Nine, overheard Palmer - who had assumed command of Gamma-Six upon Sgt. Pham's death - questioning the lack of extraction. Command informed Gamma-Six that the amount of hostiles at their position made extraction impossible, and ordered their retreat to a safer location. As two Type-26 Banshees assaulted Palmer's position, Buck ignored his orders and led Alpha-Nine to rescue Gamma-Six. By the time Alpha-Nine arrived, Palmer was the only surviving member of her squad. Together the ODST's eliminated the remaining Covenant forces assaulting their position, and returned back to base in a civilian truck.[10]

In October 2552, Lance Corporal Palmer was part of an ODST unit deployed to reinforce a UNSC outpost under attack by the Covenant. Immediately upon touchdown, Palmer single-handedly defended Admiral Kovalic, who was escaping the outpost with the base's AI. Upon emerging from her SOEIV, LCpl Palmer fought off several Covenant forces, including several Unggoy and no less than two Jiralhanae, one of which was a Chieftain. During the brief firefight she was hit by a Type-33 Needler shard, surviving thanks only to her armor. Showing ingenuity and bravery in the face of insurmountable odds - including flipping a Warthog with a grenade and eliminating a Chieftain - LCpl Palmer successfully rescued the Admiral, and was subsequently promoted to the rank of Corporal with intentions of a rapid promotion to Sergeant.[3][note 1]

Becoming a SPARTAN-IV
In January 2553, following her promotion to Corporal, Palmer received medical care for her injuries sustained in the rescue of Admiral Kovalic aboard the Lockhart medical station. There she was approached by Jun-A266, a former SPARTAN-III. Due to her preceding mission and service record as a whole - though her leadership was a major factor in her candidacy - Jun offered her a place as the first recruit for the Office of Naval Intelligence's SPARTAN-IV program.[3][7]

Though initially expressing incredulity towards the offer, Palmer accepted and joined the Spartans. She and four other candidates - Edward Davis, Yeong-hao Holst, Vladimir Scruggs, and Joel Thomas - underwent a series of biological and chemical augmentations that lasted three weeks. Following the two days it took them to adjust to the enhancements, Palmer and her fellow Spartan IV's trained under the supervision of Jun-A266 and Musa-096, a former Spartan II who was largely responsible for the formation of the program. During a simulated engagement with a squad of fifty Marines, Palmer displayed an overzealous desire to complete the objective, rushing forward at the expense of her teammates. Jun expressed embarrassment at the Spartans' poor performance, to which Spartans Scruggs and Thomas pointed out that they lacked the fabled Spartan armor. Musa-096 then addressed the squad, informing them that they would receive their armor when they deserved it. He impressed upon them their new ranks and roles as Spartans, singling out Palmer as an example that Spartans do not rush ahead and seek glory for themselves. Palmer would take this lesson to heart.[4]

Later that month, the Spartan-IV's were transferred aboard the UNSC Infinity, currently undergoing the final stages of construction in the Oort cloud. These five Spartans were the only ones aboard the ship at the time, though Infinity would later maintain a complement of up to three hundred Spartans after her shakedown cruise.[4]

Rebel incursion on Infinity
During Palmer's transfer to the Infinity, a group of Insurrectionists led by Ilsa Zane — a former participant in the prototype phase of the SPARTAN-IV program — captured Captain Andrew Del Rio and the bridge crew, in addition to disabling the ship's AI, Aine. Palmer asked Commander Thomas Lasky, the ship's executive officer, if the Armor Bay was operational enough for the Spartans to arm themselves. While it was operational, Lasky informed the Spartan that armor selection was limited. Choosing function over form, Palmer selected a suit of GEN2 Scout armor, which would remain her armament from that point on. Jun objected, informing Palmer that she wasn't cleared for a suit of MJOLNIR armor, to which she repeated Musa's words that they were Spartans, and it was time to "start acting like it."[4] Palmer and Davis repelled the takeover attempt, distinguishing themselves during the engagement.[7] The two Spartans made their way to the bridge along the exterior hull of the ship, while the remainder of the squad reached a security panel to give Del Rio access to the bridge. Upon breaching the bridge, causing a decompression of the cabin, Palmer engaged Zane in hand-to-hand combat. Despite Zane's superior physical augmentations, Palmer got the upper hand and knocked the rebel leader out of the ship's airlock with the assistance of Aine after she was reactivated by Captain Del Rio.[11]

Draco III rebellion
In 2554, during the resettlement of Draco III, the United Rebel Front attacked the capital city of New Albany in an attempt to take control of the planet. Palmer and several other SPARTAN-IVs were tasked with eliminating the insurgents throughout the city, while ODST squad Alpha-Nine was ordered to eliminate URF Captain Ingridson in the city's capitol building. However, the ODSTs' mission resulted in a stand-off between the insurgents and Alpha-Nine. Palmer offered to assist them, but Buck declined as he was afraid that their appearance would lead to Ingridson executing the captured "rookie".[12]

Palmer later warned Buck of more URF soldiers moving in on Alpha-Nine's location, but Buck was unable to respond as he had removed his helmet in an attempt to humanize himself to Ingridson. When Alpha-Nine was given the opportunity to engage the insurgents, Buck requested for Palmer and her Spartans to cover their backs from the incoming rebel soldiers. Once all rebels in the area were killed or captured, the two teams met up in the capitol building's main hall.[13] Palmer's success in the SPARTAN-IV program partially inspired Buck to join himself.[14]

Battle of Draetheus V
In 2554, Palmer and Davis were stationed on X50, Draetheus V's moon, where they defended against Merg Vol's Covenant forces. Palmer and a contingent of Marines worked to destroy Covenant artillery on Mirror Flats on the moon. Despite the efforts of the UNSC forces, the Covenant managed to surpass them in less than an hour, forcing Palmer to go to Draetheus V to inform the planet of the impending attack while Davis led the UNSC defensive on X50.[15] On Draetheus V, Palmer led the UNSC forces in the defense of Faraday Base and later eliminated several Sangheili commanders.[16]

The Covenant forces soon discovered that the X50 was a former Forerunner installation capable of planetary destruction and used it on the planet. With the planet on the verge of collapse, Palmer, with a handful of UNSC forces, assaulted the Covenant landing zones on the planet and took over the Covenant ships to evacuate the planet.[17] Soon, after Spartan Davis was killed by Sangheili forces on the moon, Palmer led an operation to eliminate Merg Vol. By appropriating one of his lieutenants' ships, Palmer managed to infiltrate the Covenant base on X50 and remove Merg's lieutenants before facing Merg Vol himself at the activation site. Despite the impossibilities, Palmer engaged Vol and his Kig-Yar reinforcements. After a long skirmish, Palmer executed Merg Vol with her M6H magnum and destroyed the artifact. After this, Palmer and the remaining Marines escaped the moon moments before the artifact was sabotaged.[18]

Some time later, Palmer returned to X50 after discovering a Forerunner signal from inside the "moon". Tracking the source of the signal, Palmer fought through the remaining members of Merg Vol's Covenant. After arriving at the source of the signal, she discovered that source were the remains of Edward Davis, who had died during the battle. The installation disintegrated Davis's corpse and encapsulated it in an unknown device, and with the help of a D77H-TCI Pelican, Palmer took the remains of her comrade with her.[19]

First tour on Requiem
In July 2557, Palmer was stationed aboard Infinity and was the commander of the three hundred SPARTAN-IVs aboard the vessel. Infinity intercepted a distress beacon from the UNSC Forward Unto Dawn near the Forerunner shield world Requiem; the remains of the vessel carried MCPO John-117, one of the few remaining SPARTAN-IIs, as well as his AI companion Cortana.[21] Infinity was soon drawn inside the shield world, where its Spartan contingent was deployed to battle both local Promethean constructs under the command of the Didact, as well as Covenant forces. The Master Chief rendezvoused with the Spartans under Palmer's command and eventually made his way aboard Infinity.[20] Palmer later sent Gypsy Company to aid the Master Chief and Lasky in an attack on the gravity well generator, but did not participate in the battle herself. Later, when the Master Chief refused to hand over Cortana aboard Infinity, determined to stop the Didact alone, Palmer and the rest of the bridge crew ignored Captain Del Rio's orders to stop the Master Chief, allowing the SPARTAN-II to leave without attempting to stop him.[6][note 2]

First missions
In February 2558, Infinity was deployed back to Requiem.[5] On February 8, Palmer authorized Operation: ALL-SEEING EYE, which entailed Fireteam Majestic's deployment to the surface to recover a Forerunner artifact.[22] She also deployed Fireteam Crimson with a similar objective in support of Majestic; Crimson eventually recovered the artifact. After the artifact was brought aboard Infinity, it suddenly emitted an energy pulse and started draining power from the ship. When the artificial gravity was disabled, Palmer magnetized her boots to stay on the ground. She then ran at the artifact and kicked it, temporarily deactivating the device. After Doctor Henry Glassman began examining the artifact it reactivated, pulling Dr. Glassman inside it through a portal. Captain Lasky attempted to save Glassman, but Palmer noticed he was being pulled in as well and tackled him, keeping him out of harm's way.[23]

After the incident, Doctor Catherine Halsey was brought in to examine the artifact in Glassman's absence. Palmer expressed particular disdain for Halsey, believing that ONI incarcerated her for a reason. Her suspicions were not entirely wrong, as it was later revealed that Halsey was secretly communicating with someone. After this discovery, Lasky ordered Palmer to arrest Dr. Halsey. She was not heard from for some time, forcing Jared Miller to run Spartan operations with Infinity AI Roland in her absence.[24][25]

Palmer eventually returned to run operations again, and later held off the Covenant/Promethean forces when the alliance attempted to retake the artifact that Crimson had recovered.[26][27] However, she failed to realize the true goal of their invasion until it was too late: while arguing with Dr. Halsey, a Promethean Knight translocated behind her and temporarily incapacitated her before taking Dr. Halsey. Angered by this, Palmer slammed down on the holo-table, denting it, and left the bridge.[28]

Further operations
She later returned to running Ops just as Crimson was redeployed to the Apex. She ordered Crimson to shut down three slipspace portals in the area, while Miller detected an SOS Morse code signal on a Covenant frequency. After Crimson secured the Apex for Fireteam Lancer, Palmer sent Fireteam Crimson to assist Majestic who were under attack from Covenant artillery and needed assistance.[30] As they arrived at the artillery's location, Miller told her the Covenant seemed prepared for them, as if they knew they were coming; she told him not to be paranoid. However, after Crimson had destroyed all of the Covenant's artillery, Palmer's suspicions increased. After eliminating hostiles, Crimson left to regroup with Fireteam Lancer to attack a recently-discovered Covenant base in the Warrens.[31] While the two fireteams were attacking the base, Miller picked up the mysterious SOS signal again, originating from a nearby cave. Lancer and Crimson made their way into the cave and discovered the source of the mysterious SOS signal was from Fireteam Switchback, who were being held prisoner by the Covenant. Shortly after, the Spartan fireteams were extracted.[32] After interrogating a Sangheili, Palmer sent Crimson to the area where the Covenant was intercepting UNSC transmissions. Crimson soon discovered a captured Army Pelican that was being used to listen in on UNSC communications. After Crimson cleared the area, Palmer had Dalton destroy the dropship.[29]

Later, Doctor Henry Glassman needed help reading the holographic map of Requiem that Spartan Anthony Madsen recovered from Gek 'Lhar. Palmer ordered Crimson to check out a location marked by Spartan Gabriel Thorne. Glassman used the map to help Crimson activate a friendly automated defense turret grid and heavy weapons; Palmer was impressed with this. After finding a stockpile of Promethean heavy weapons, Miller had Crimson evacuated.[33]

Assassin for ONI
When orders from Admiral Serin Osman came down to kill Dr. Halsey, Palmer decided to carry it out personally. Lasky attempted to stop her, voicing his protests against ONI using the conventional military to carry out their assassinations, particularly when the target was a civilian. When Lasky continued to protest, Palmer said she wouldn't see him court-martialed because of Halsey. Lasky finally ordered her to stand down, but she ignored him, responding that orders were orders.[34]

She eventually made her way to Halsey's position, quietly taking out Sangheili guards with her combat knife. She made it into the "shrine" shortly after Gabriel Thorne had, killing an Sangheili about to sneak up on him. She tried to shoot and kill Dr. Halsey but hit her in the shoulder. Promethean Knights started to translocate into the area and she was forced to engage them. The rest of Fireteam Majestic showed up and engaged the Knights, Palmer attempted to make her way to Halsey. However, just as she and Thorne were about to reach her a Promethean Knight translocated in behind 'Mdama and escaped with him and Halsey. She yelled in frustration and asked why Majestic was there, DeMarco told her Captain Lasky had ordered them to rescue Dr. Halsey. She questioned why he would do that when she was a traitor. Thorne then told her about how Halsey made sure he got half of the Janus Key.[34] She then redeployed all Spartan fireteams to help in recovering Dr. Halsey.[35]

Escaping Requiem
After the events in the Librarian's shrine, she and Fireteam Majestic were sent the deactivation codes of one of the Requiem slipspace artifacts in order to free Infinity from Requiem's orbit, while Fireteam Crimson deactivated the third. Suddenly the Covenant fleet flew overhead and left Requiem, entering slipspace just outside the exterior shell. The entire planet then began to move towards the system's sun and Palmer quickly ordered Majestic to move out.[36]

Later, after Crimson retrieved a new power supply for the Harvester, Miller informed Commander Palmer that they were back at the Harvester. She informed Miller that she and Majestic were almost at their objective as well. She asked Dalton about the evacuation of the planet and he informed her that everyone else was onboard and that Crimson and Majestic were the only ones left on the planet. After activating the Harvester and opening a path to the artifact, Miller reported to Commander Palmer that they had a path to the artifact. Palmer told him to just tell her when Crimson had finished and then yelled at DeMarco to check his six. She congratulated Crimson after they deactivated their artifact.[37]

Shortly after this, Captain Lasky asked how things were going she reported that Crimson had accomplished their mission, but Majestic was still working on theirs. She covered Thorne as he deactivated the device, once they cleared the area and deactivated the artifact they evacuated. Palmer and Tedra Grant piloted their Pelican back to Infinity and arrived at the ship at the same time as Crimson. After they had successfully escaped, Palmer and Lasky visited Dr. Glassman's lab, where the doctor was studying the incomplete Janus Key. On the way there, she reproached Lasky for ostensibly sending Majestic to stop her. Lasky responded that he sent Majestic rescue Halsey, but Palmer saw no difference.[38]

Battle of Ealen IV
Upon Infinity's return to Earth, Palmer was requested to appear before the UNSC Security Council at HIGHCOM Facility Bravo-6 along with Captain Lasky. There, she and Lasky were debriefed about the Second Battle of Requiem. Admiral Serin Osman berated Lasky over the complete destruction of Requiem and the failed assassination of Dr. Halsey. Osman then asked Commander Palmer if Lasky had deliberately sent Fireteam Majestic to stop her from eliminating Halsey. To protect Lasky from any ramifications, Palmer lied to Osman and claimed that Majestic was there for backup.

Shortly after, Palmer, along with Fireteams Jackknife, Bailey, and Paul DeMarco of Fireteam Majestic, was assigned to escort and provide security for Fleet Admiral Terrence Hood and Kaidon Thel 'Vadam on a diplomatic mission to Ealen IV. While Hood and 'Vadam were negotiating with the Jiralhanae Chieftain Lydus, Covenant mercenaries broke into the chamber and attacked the delegates. She ordered Jackknife to clear the chamber and help the delegates evacuate, and ordered Bailey to clear a path to the evac shuttle. When the ship was destroyed by Banshees, the team proceeded to escort the delegates to a nearby parts depot.[40]

Inside the repair depot, 'Vadam notified the rest of a decommissioned redoubt in which they could take refuge in. Lasky then ordered Palmer and the protection detail to escort the delegation to the redoubt, while he would try to re-establish communications with the fleet above the planet. Palmer refused to let him go alone and tasked Spartan Naiya Ray of team Jackknife to escort the captain due to her SIGINT background. As the party escaped the storage depot, they were intercepted by a Covenant Lich. Palmer quickly acted and ordered everyone to give her their grenades. She put all the grenades in her helmet, which she then threw at the Lich, destroying it. As she and the others retreated to a gravity lift, a surviving enemy Sangheili grabbed her. Scruggs killed the Elite just in time.[39] As Lord Hood halted the party to inspect the fallen Sangheili, Palmer told Scruggs to take Jackknife ahead with the delegation's bodyguards to ensure that the redoubt was safe to use as shelter. Hood discovered the Elite possessed detailed UNSC profiles and informed Palmer that someone within the UNSC was leaking information to the Covenant. After hearing gunfire coming from the redoubt, Palmer asked Jackknife to report in. Through a transmission mired with static, Scruggs informed her that the area was secure. Unbeknownst to her, Scruggs had turned on them and murdered the bodyguards and his fireteam.[39]

Arriving at the redoubt, Palmer ordered DeMarco's team to sweep the courtyard and provide an inventory of supplies. As they proceeded onwards, Scruggs ambushed the delegates and held Lord Hood hostage at gunpoint. Palmer, surprised by his change of loyalty, asked whether he was an Insurrectionist. Scruggs scoffed at her assertion and told her that she was oblivious to the UNSC's secret role in regards to the New Phoenix Incident, ONI's campaign against the Sangheili and John-117's recent disappearance. Palmer then shot Lord Hood in the leg and tackled Scruggs out the mezzanine. After a brief struggle, Palmer killed him by stabbing him in the throat with a combat knife. She was contacted by Lasky who informed her of Covenant ships inbound to their site. She was ordered by Lasky to escape with the ambassadors on a transport craft while DeMarco and Fireteam Bailey remained behind to cover their escape with a Tyrant AA gun. Palmer reluctantly obeyed and asked DeMarco if she could do anything for him. DeMarco asked her to return a book Anthony Madsen had loaned to him, and he then parted ways with her. Palmer and the delegation managed to escaped back to Infinity thanks to their sacrifices. Palmer later attended a memorial service held for the fallen Spartans of the battle. Afterwards, Lasky tried to comfort Palmer about the deaths of her comrades but she asked to be left alone.[41]

Pilgrims' Pride and Oth Lodon
On March 11, six days after DeMarco's death, Infinity arrived in the Artesia-702 system having received a distress signal from the damaged freighter Pilgrims' Pride. When the freighter was tugged inside Infinity, an ambush was sprung as the freighter set itself to self-destruct and multiple UNSC assault crafts exited its cargo bay. With the help of SPARTAN-IVs the attack was repelled. Following the attack, Infinity learned that the assault crafts from the freighter belonged to the long-lost UNSC Spirit of Fire.[43] Roland discovered that the freighter was launched near Oth Lodon, a gas giant located deep in Jiralhanae space. With the Spirit's possible location found, Lord Hood authorized Commander Palmer to conduct a search-and-rescue mission. Equipped with OF92 Booster Frames, Palmer and Fireteam Majestic scouted the planet's system. As they entered an asteroid field, Palmer, not wanting to listen to Miller's in-mission chatter, shut down communications with Infinity under the guise of losing the signal in the asteroids. Exploring the asteroid field, the Spartans came across not the Spirit of Fire but instead a Covenant station under control by New Colonial Alliance insurgents. Palmer restored communications to inform Infinity about the discovery.[42]

As Infinity jumped next to the station, Captain Daniel Clayton, son of the renowned Captain James Cutter, revealed himself as a defector and fired the station's glassing cannon at Infinity. With damaged sustained to the ship and communications down, Palmer and Majestic proceeded to take control of the station. After evading oncoming missiles, the Spartans quickly boarded the station and secured the bridge, ordering everyone to freeze. Clayton told his crew not to listen and asked the Spartans if they knew who he was. Madsen responded saying he knew who he was and knocked Clayton down for being responsible for DeMarco's death. The Spartans then turned their attention to Vata 'Gajat, who was preparing to assault the crippled Infinity. With the station's cannon back online, they fired on 'Gajat's flagship, destroying it and saving the Infinity.[44]

Three days later, Lasky returned to Infinity, having been successful in uncovering Clayton as the spy but failing to report it to the UNSC in time to prevent his attack. Palmer welcomed Lasky on board and apologized for her behavior following the events on Ealen IV. Lasky accepted her apology and expressed guilt for not uncovering Clayton's plot fast enough. Palmer assured him he was not to blame as it was Lord Hood who had taken off without his consent. She told Lasky to just call it a rough day and to move on.[44]

Bioweapon incident
On May 10, 2558, Captain Lasky consulted with Palmer about a situation unfolding on Ven III. Infinity had lost communications with Spartans Naiya Ray and Gabriel Thorne, who had been deployed on the planet on a mission to capture a Sangheili in possession of a new biological agent. While Lasky proposed that they dispatch another two-man team to exfiltrate the Spartans already on the ground, Palmer stated that his initial decision to send in a reduced force was a mistake and insisted that they deploy a full fireteam or do not act at all. While Lasky was at first hesitant, he finally yielded to Palmer's and Roland's suggestions after Spartan Ray discovered a large black market and pirate stronghold moments before her signal briefly terminated.[46]

After the majority of the pirate fleet was destroyed by Infinity, Palmer and Majestic were deployed into the remains of the pirate base and battled through numerous Kig-Yar pirates. Meanwhile, Ray rescued Thorne from the Sangheili that had captured him earlier. When the Sangheili managed to escape, Ray pursued him and gave Palmer Thorne's location to allow Palmer and Majestic to extract him from battle. However, Palmer informed Ray that she was redirecting Majestic to Ray's location to help her capture the Sangheili. Instead, Ray shut down her locater to force Palmer and Majestic to rescue Thorne instead. After Ray recaptured the Sangheili, ONI agents arrived at her position and took control of the operation. The Spartans returned to Infinity, and Lasky and Palmer discussed the aftermath of the mission. Lasky theorized to Palmer that ONI staged the bioweapon incident to lure Infinity to Ven III to destroy the pirate stronghold. Confused over the situation, Lasky asked for Palmer to never let him forget the aftermath of the mission.[45]

Janus Key conflict
On July 16, 2558, Commander Palmer participated in the Battle of Oban against Jul 'Mdama's forces. Desperate to find Jul, Palmer and Thorne drove a Warthog and engaged Promethean forces. Palmer recklessly drove the Warthog off of a cliff, landed on a Phantom dropship, and crashed to the ground. Thorne was injured in the process and the Spartans were only saved after the Phantoms were destroyed by a GA-TL1 Longsword called in by Spartan Joel Thomas. After a short engagement, the Covenant forces withdrew from the system. The next day, Lasky reprimanded Palmer for her reckless behavior on Oban and recognized that Palmer was so intent on finding Jul because she knew that he would lead to Halsey. While Lasky wished to return Halsey to UNSC custody, Palmer remained determined to execute the doctor.[48]

On July 18, Infinity entered slipspace to leave the Oban system while Palmer discussed preparations for Galileo II with Dr. Glassman. However, Infinity was forced back into normal space in an uncharted system. All subsequent attempts to jump failed, stranding the ship in space. Lasky met with Glassman and Palmer in the engine room of Infinity. Glassman discovered that something was overriding the engine controls of Infinity, while Roland reported an unusual energy reading coming from a nearby planet. Glassman and Lasky predicted that the source of the problem originated from the planet, and Palmer prepared to gather a team to send to the planet with Glassman. Meanwhile, 'Mdama and Halsey planned to intercept Infinity and retrieve the other half of the Janus Key. Using a Forerunner artifact to interfere with the engines of Infinity, Halsey believed that the crew would be willing to hand the Key over willingly.[48]

Palmer, along with Majestic team, were deployed to investigate a potential source of interference emanating from the surface of a nearby planet, provisionally designated Aktis IV. Upon landing on an island, the Spartans engaged and defeated a detachment of Covenant forces and subsequently discovered a recently-excavated Forerunner structure. Dr. Glassman arrived on the surface of Aktis IV to examine the Forerunner structure, with the Spartans providing cover. Glassman theorized the structure to be part of a translocation grid and soon discovered a Forerunner artifact that was seemingly compatible with the Janus Key. Unknown to Glassman and the Spartans, the artifact was in fact a decoy created to by Halsey and 'Mdama deceive the UNSC into taking their half of the Janus Key to the surface. Glassman requested to have lab equipment brought to the Forerunner site along with the UNSC's half of the Janus Key in order to analyze the artifact; although hesitant, Palmer reluctantly agreed and contacted Lasky. As the Pelican carrying the Key approached the Forerunner site accompanied by a Broadsword escort, the UNSC craft were suddenly struck by Covenant anti-air artillery. This triggered a massive Covenant ambush and the Spartans were quickly forced to pull back into the Forerunner structure.[49]

Commander Palmer, Fireteam Majestic and Glassman remained under attack by Covenant forces inside the Forerunner structure and were unable to establish contact with Infinity. While they retreated inside the facility, Hoya was left behind outside. Palmer ordered Glassman to get the structure's teleportation grid online before the Covenant breached their defenses. Hours later, Ray received a transmission from Hoya, who had spotted Dr. Halsey in the jungle. After Glassman managed to activate the translocation grid Palmer ordered him to open portals to both the jungle and the other end of the island. She ordered Grant, Glassman and three other Spartans to take the latter portal while Palmer, Ray and Thorne took the former.[50]

Upon traveling through the portal, Palmer, Ray and Thorne scouted the jungle when they spotted a Sangheili Minor who had defected from 'Nyon's forces. The Minor contacted Jul's Covenant and told him he wanted to rejoin 'Mdama. He then revealed he had the half of the Janus Key stolen by 'Nyon, and he would lead them to 'Nyon's hideout. 'Mdama's forces agreed to set up a rendezvous with the defector in order to secure the Janus Key half. Thorne and Ray intended to ambush the Minor and recover the Janus Key immediately. However, Palmer instead ordered them to hold off and wait until Halsey arrived. Both Spartans questioned her order, pointing out that they should take the Janus Key from the Sangheili before a greater Covenant force arrived. However, Palmer was determined to carry out the ambush.[50]

Halsey eventually arrived, escorted by a large Covenant convoy. Ray and Thorne fruitlessly attempted to talk Palmer out of her plan, but after most of the convoy departed and the Minor handed over the Janus Key half, the trio proceeded with the ambush. While Thorne and Ray created a distraction, Palmer drove a Ghost into a Wraith in the midst of the Covenant forces. Palmer began to eliminate the Zealots guarding Halsey and gave chase as one of them attempted to take the doctor into the jungle, leaving Ray and Thorne to fend off the Covenant on their own. She killed the Zealot and took Halsey captive, finding that she could not bring herself to kill the doctor despite her original plans. While she was leading Halsey through the jungle the doctor confronted Palmer about her unquestioning loyalty to Admiral Osman. Palmer insisted that her loyalties lay with the UNSC and continued to express her utter contempt for Halsey. After Halsey revealed that ONI was using her as a scapegoat for projects that had their full support, Palmer became momentarily lost in thought over what she had been told. Using this to her advantage, Halsey ran off. Palmer gave chase but came up against a Harvester. The Covenant excavator attacked her with its plasma drill, knocking her down a cliff. Palmer attempted to propel herself back up using her armor's thrusters, only to be knocked into a narrow crevice by a falling rock.[47]

Three days later, Palmer and the other Spartans having returned to Infinity, ONI agents arrived on board to interrogate her. While Roland stalled the agents, Captain Lasky met with Palmer and asked her what had happened on the planet. Palmer told him of her failure to eliminate Halsey and secure the Janus Key, advising Lasky to prepare for the worst due to Jul 'Mdama's acquisition of both halves of the Janus Key.[47]

The Absolute Record
After the battle at Aktis IV, Palmer began to triple her required hours in War Games simulations. On September 15, 2558, Admiral Osman organized a team consisting of Spartans Palmer, Thorne, Holly Tanaka, Dr. Glassman, and Ayit 'Sevi. Lasky then briefed the team on Operation: ATHENA, a mission in which the team would enter Covenant carrier Breath of Annihilation in a Phantom operated by 'Sevi, who had infiltrated 'Mdama's ranks. Once aboard, the team would wait until 'Mdama's fleet—including the carrier—arrived at the Absolute Record and then use a telemetry probe to transmit their location to the UNSC. Despite Lasky's concerns about Palmer's priorities due to her personal feud with Halsey, Palmer felt she was fully up to the task. On September 17, 2558, the team entered the carrier just as the fleet left for the Absolute Record's supposed location. Upon arriving at an artificial gas giant, a slipspace portal to the installation began to open. However, slipspace ruptures suddenly materialized and destroyed two cruisers and damaged Annihilation, destroying the telemetry probe in the process.[52]

The team was forced to flee their damaged dropship and fight their way through Covenant forces in a corridor in order to reach an undamaged hangar bay. 'Sevi soon procured a Phantom and transported everyone directly to Jul 'Mdama's flagship, Song of Retribution. With news that 'Mdama intended for Retribution to push forward through the portal alone and reach the Absolute Record, the team resolved to split-up. While Palmer, Tanaka, and Glassman remained on Retribution, Thorne and 'Sevi returned to Annihilation in an attempt to regain contact with ONI. After Thorne and 'Sevi departed, Retribution entered the portal and arrived at part of the Absolute Record, where a Contender-class artificial intelligence detected the humans aboard the carrier.[53] The carrier was soon forced into a slipspace portal, where it arrived at a large chamber inside the installation and was held in place by a gravitational anchor. While 'Mdama, Halsey, and a contingent of Zealots traveled to a lower platform where the AI was, Palmer, Tanaka, and Glassman waited for their chance to escape the carrier. However, confused by their need to conceal themselves, the custodian AI had its Sentinels transport the Spartans and Glassman down to the platform beside Halsey and the Sangheili. When an argument broke out between both sides, the AI silenced them and stated its intentions to allow each human account for their presence at the installation. While the AI began questioning Glassman, an impatient Zealot attacked a Sentinel, despite Palmer's warnings. As a firefight broke out between the Sentinels and the Sangheili and humans, the AI removed the flooring from under the Sangheili's feet, with Tanaka, Palmer, and Glassman remaining on one platform and Halsey standing on another, while 'Mdama managed to grab onto Halsey's platform while the Zealots fell to their deaths. The AI insisted that a more direct examination was in order to decide who the legitimate steward of the Absolute Record was.[54]

Separating the survivors into two groups, the ancilla tested both of them with a hypothetical scenario, if they would sacrifice sapient species if it meant a vaccine against the Flood. However, Halsey grew impatient and disabled the AI, taking control of the Absolute Record herself.[55] Palmer and her teammates found their half of the simulation interrupted, and soon were surrounded by Jul 'Mdama's reinforcement warriors. However, they were rescued by a Sentinel with the voice of the custodian AI, which explained that it was a backup in case the main body was shut down.[56] Needing their help to regain control, the Sentinel directed Palmer, Tanaka, and Glassman to the auxiliary control conduit, where Palmer received the initialization code from the AI and read it for Glassman to type. However, Halsey realized what they were up to and remotely deterred their attempt. Informed that Halsey was in the room directly above them, Palmer traveled up there and gave Halsey three seconds at gunpoint to step away from her control console. Instead Halsey activated a containment field around Palmer and fled into a portal.

Battling Sentinels, Jul 'Mdama ordered the Song of Retribution to fire into the Record, disrupting power across the facility. Palmer's containment field failed, and she broke free while the revived custodian AI intercepted Halsey. With the Record falling apart, Palmer regrouped with her teammates and made a hasty escape through the Record's teleportation grid, Glassman directing it to deposit them inside the parked Breath of Annihilation. There 'Sevi found and hid them while the carrier flew back to Sangheili space, where the humans covertly fled and were picked up by an ONI prowler. Palmer was debriefed afterward about the mission by Lasky, and remarked on Halsey's unusual behavior when Palmer confronted her. Having not killed Palmer when she had the chance and instead overplaying for capture, Palmer considered Halsey humiliated enough to satisfy her.[51]

The Guardians
In October 2558 Commander Palmer briefed Fireteam Osiris on the mission on Kamchatka. She tasked Osiris to bring Dr. Halsey back to Infinity and terminate the Covenant supreme leader Jul 'Mdama were they to gain the opportunity to do so.[58] Upon Osiris's successful return with Dr. Halsey Sarah Palmer escorted her to the command deck where the doctor briefed Cpt. Lasky, Palmer and Roland about Cortana's survival and her control of Forerunner artifacts through the Domain.[59] After the incident on Meridian Palmer was also present when Jameson Locke reported that Cortana was activating the Guardians, enormous Forerunner constructs, which caused significant destruction and civilian casualties on human colonies. When they discovered yet another dormant Guardian was on the Elite homeworld of Sanghelios, Palmer suggested that they send a ground team down to the planet to access the Guardian in order to get to the Master Chief and Blue Team who went AWOL to find Cortana.[60]

Upon their arrival at Sanghelios, Sarah Palmer, along with Dr. Halsey and Fireteam Osiris, were escorted by a Sword of Sanghelios to the Arbiter while he was engaged in combat. After a quick firefight, the Spartans and Dr. Halsey were taken to the Arbiter's base camp. There they acknowledged that the Guardian was in Sunaion, the Covenant's last stronghold. To gain access to the Guardian the Spartans had to obtain Constructor, which could interface with the Guardian and delay Cortana's control of it, lessen the damage at its point of exit, and slow it down so Osiris could board and follow the Guardian.[61] During the Constructor's extraction Sarah Palmer provided Osiris with transportation and battlefield support. After the retrieval of the Constructor Palmer returned to the Arbiter's base camp to prepare for their assault on Sunaion.[62] During this joint Spartan-Sword of Sanghelios operation she escorted Dr. Halsey aboard the Pelican while the Osiris and Arbiter's forces were fighting on the ground. During the ensuing battle, the Guardian was awakened. Palmer ordered Fireteam Osiris to board her Pelican so she could deliver them to the Guardian. Though their Pelican was hit by a Banshee, Osiris managed to board the Guardian which transported them to Genesis. Jumping into the slipspace the Guardian launched an EMP attack which shut down Palmer's Pelican, making them fall straight towards the ocean. [57] The Swords ended up winning the battle, putting an end to Jul 'Mdama's Covenant once and for all. Sarah Palmer and Dr. Halsey managed to survive their crash-landing with Palmer seriously wounded and her MJOLNIR armor heavily damaged.[63]

After the battle Palmer, Dr. Halsey, the Swords, and the Arbiter headed back to base camp. When Osiris got Blue Team back from Cortana, they brought them to base camp. Palmer and the rest of the group watched as the Master Chief exited the Pelican and once again met Dr. Halsey and the Arbiter.[63]

Personality and traits
Palmer possesses a strong sense of duty, displaying great tenacity and boldness on the battlefield. Possessing an audacious, gung-ho attitude, she is regarded as an experienced and capable leader and is generally cool in tense situations. At the same time, she does have a tendency to react badly when things go wrong. For instance, when Doctor Catherine Halsey was abducted from the bridge of the UNSC Infinity, a frustrated Palmer punched a nearby holo-table so hard her fist dented the metal.[28]

Palmer takes great pride in being a Spartan, to the point of looking down on the conventional military branches; despite her own ODST roots she frequently shows rather low expectations of Marine personnel. In contrast, she has very high expectations for her Spartans, especially those of Fireteams Crimson and Majestic. Palmer typically performs her job in a no-nonsense manner and does not hesitate to dress down her fellow Spartans when they fail to meet her expectations. Several times she called out Fireteam Majestic's leader Paul DeMarco in front of his own team.[5][64] Spartan Jared Miller once remarked that it is rare for Palmer to praise anyone under her command. However, she does have a dry sense of humor which she occasionally exhibits on the job. Furthermore, she takes pride in the Spartans under her command and encourages both cooperation and competition between the various Spartan fireteams. She even teased John-117 about his height when she met him on Requiem.[20]

Palmer regards scientists with a general disdain, demonstrated by her frequent irritation when having to deal with science teams and her incessant use of the derogatory term "eggheads". This is because she views those with an academic education as pretending to be more intelligent than her, a perceived sense of superiority which in her view is not shared by her fellow military personnel.[3] She reserves particular contempt for Dr. Halsey due to the doctor's reputation as well as the doctor's own lack of respect towards Palmer and the other Spartan-IVs. However, Palmer is willing to give scientists credit where it is due. For example, she was genuinely impressed by Dr. Glassman when he enabled Fireteam Crimson to activate a pair of friendly Forerunner anti-aircraft guns to assist them against the Covenant.[33] Palmer is rather reserved in her relationships with others. The only two people she is known to have developed close personal ties to are her teammate Edward Davis and Captain Thomas Lasky. When Davis was killed, Palmer mourned him and took it upon herself to recover his remains.[19] She and Captain Lasky often refer to each other on a first-name basis and Palmer shows a great deal of concern for his well-being. Most notably, Palmer's motivation for following ONI's orders to kill Dr. Halsey (besides genuinely believing that Halsey was a traitor) was to protect Lasky from being court-martialed for refusing to carry out the order, even when this meant outright ignoring Lasky's direct order to stand down.[34] Later, she lied to Admiral Serin Osman in order to protect Lasky, claiming that Majestic was sent as a backup team, not to stop her.[40] Palmer and Lasky's friendship became strained following the deaths of Paul DeMarco and several other Spartan-IVs on Ealen IV. When Lasky tried to talk to Palmer she angrily lashed out at him and said she did not want to talk to him.[41] The two eventually reconciled following the battle at Oth Lodon, with Palmer apologizing to Lasky for her outburst.[44]

Equipment
Palmer wears the Scout variant of the MJOLNIR GEN2 armor, in lieu of specialized communications models built specifically for Spartan officers, with Inner-Plated forearms and Outer-plated legs. She favors using a pair of M6H magnum sidearms.[65] Additionally, Palmer often arms herself with a M395 DMR.[40]