Thel 'Vadam

Were you looking for the Arbiter Ripa 'Moramee from Halo Wars, Thel 'Lodamee from The Package, or the Halo 2 campaign level The Arbiter?

Thel 'Vadam (formerly Thel 'Vadamee), often simply referred to as the Arbiter, is the deuteragonist of Halo 2, a supporting protagonist in Halo 3, and the most prominent Sangheili shown throughout those games.

Early life
Thel was born Thel 'Vadam to the Vadam family, rulers of the powerful State of Vadam on Sanghelios. As a young Sangheili, Thel was trained in the ways of the warrior by his relative Lak 'Vadamee. He joined the Covenant military, earning him the right to use the "-ee" suffix, which is added to a Sangheilian name upon joining the military. Thel fought alongside the Covenant when they attacked Madrigal in 2528.

Soon, Thel gained the rank of Shipmaster and earned the title of Kaidon within his keep.

Soon after being promoted to Shipmaster, Thel suffered an injury in the training ring due to a mistake. His family hushed up the incident, as well as the resultant visit by a doctor, due to Sangheili culture equating the loss of blood and medical operation by a doctor with a loss of honor. During his convalescence, Thel made an old-fashioned doarmir-fur Shipmaster's cloak, wearing it always to remind him that he could make grave mistakes if he let his guard down.

Life as Kaidon
"It is a poor soldier who insists on seeing things not as they are, but as he wants them to be. One day reality hits, and his illusions fail him, and he dies stupidly. What honor is there in that?"

- Thel 'Vadamee

Thel's life as Kaidon was important for the Vadam family, as he was tasked with continuing the reign of the powerful State of Vadam. Early in his rule, he was attacked by three Sangheili assassins wielding Energy Swords. He managed to kill all three without even being scratched, but bluffed that he left one alive in order to determine who ordered the attack. He then killed one of the Vadam elders, Koida, for ordering the failed assassination, and ordered all of his line to leave the keep by sunrise or they would otherwise face execution.

Thel was sent to Charybdis IX with command over Retribution's Thunder to participate in the Battle of Charybdis IX, whilst being overseen by the High Prophet of Regret. He and several other Sangheili boarded the and attempted to get to the vessel's navigation database, but it had been purged before they were even aboard. He left and witnessed the destruction of the ship before being called to the Infinite Sacrifice, where he met Regret in person. He was told of the humans wielding modified Covenant weapons, and that this was most likely the Kig-Yar's doing. He was then sent to the 23 Librae system to track down the source of the weapon traders, along with the Kig-Yar vessel, A Psalm Every Day.

As he arrived at 23 Librae, his ship came under attack, first by Jiralhanae and Kig-Yar forces at The Rubble, then boarded by  A Psalm Every Day' s forces. He ordered the destruction of The Retribution's Thunder, which killed all the boarding Kig-Yar. Thel, however, survived and was captured by Kig-Yar forces, along with most of the bridge crew. He and the bridge crew managed to escape and hijack a Kig-Yar shuttle, taking them to another Kig-Yar vessel. They went to the surface of Metisette and captured the leader of the Kig-Yar, Reth.

After managing to escape Reth's clandestine Unggoy army, Thel returned to the Kig-Yar vessel, where they locked up Reth. Interrogating him, the Sangheili were surprised by Reth's insistence that he was allying with the humans with the blessing of the High Prophet of Truth, who sought to use the humans as a means to find their homeworld. He eventually escaped when a nervous Grunt still loyal to him, switched off the energy barrier, and fled into an escape pod. Thel then turned his eyes to The Rubble, as a large skirmish between UNSC forces and Kig-Yar forces was taking place on the Infinite Spoils. He and his crew then boarded the Infinite Spoils and came face to face with Jai-006 before fighting with him. The SPARTAN tackled Thel, disarmed him of his Energy Sword, and proceeded to draw a combat knife. The two warriors eyed each other for a brief moment before the SPARTAN, realizing that the marine he came to rescue was already dead, left the ship with the other UNSC forces. Thel and his crew, shocked by what they had witnessed, stayed and commandeered the Infinite Spoils.

Thel managed to destroy most of The Rubble's Mass drivers, but then was helpless when The Redoubt was destroyed and the Exodus Project left the system. He decided the best thing to do was to wait for the High San 'Shyuum of Truth and Regret to arrive and report to them with his comrade, Zhar. Upon reporting the failure of the mission, Zhar attempted to slaughter the San 'Shyuum — believing them to be ordering his execution — but Thel activated his own Energy Sword and killed his former friend. This act prompted Truth to spare his life and give him command over a ship in the Fleet of Particular Justice, a newly assembled fleet for the Covenant Navy.

Life as Supreme Commander
"Soon the Great Journey will begin, but when it does, the weight of your heresy will stay your feet, and you shall be left behind."

- The Prophet of Truth to Thel 'Vadamee at his hearing.

At some point between 2535 and 2552, Thel's exceptional leadership and combat prowess earned him the rank of the Fleet of Particular Justice's Supreme Commander. During his time as a Supreme Commander, Thel was responsible for over 1 billion human casualties, the loss of at least 7 human worlds, the destruction of over 123 human vessels during fleet action and the deaths of over 23,000 UNSC personnel.

Near the end of his time serving as Supreme Commander, he led the victorious Covenant forces at the Fall of Reach. As the battle ended, Thel ordered all ships within his command to follow the fleeing. Following the  Autumn' s course led them to Installation 04. Commanding the Seeker of Truth, he had his ships begin evacuation of the ring upon the release of the Flood, but the parasite managed to capture a ship and infect a Minor Prophet, the Minister of Etiology. The sudden widespread evacuation led to confusion as ships became infested, and he was unable to prevent the destruction of the ring and was forced to abandon it. The abandonment saved his life, but also resulted in the capture of the newly arrived flagship, the Ascendant Justice, by John-117, and he was called before the High Council to answer for these failures.

The loss of the Forerunner relic that the Covenant held "holy" rendered the Council unmoved by his defense, and 'Vadamee was stripped of his rank, title, name, honor, and branded a heretic for his failure in safeguarding Halo. The Mark of Shame was branded upon his chest in front of many of the Covenant, and he was sentenced to death. He was sentenced to "be hung by his entrails" and his corpse "paraded through the city" as an example to others. The Prophet of Objection went so far as to say "it was heresy."

Upon being brought to the Prophet Hierarchs of Truth and Mercy, they intervened and offered to commute the sentence if he would become the new Arbiter. Understanding that becoming the Arbiter of the Covenant amounted to an indirect death sentence, but also seeking an opportunity to redeem his name to retain honor for his continuing bloodline, the Sangheili accepted the offer.

Gas Mine
"What would you have your Arbiter do?"

- 'Vadamee to the Prophets



'Vadamee's first combat assignment as the Arbiter was to stop the Heretic uprising based in a Forerunner Gas Mine in the atmosphere of Threshold. The San 'Shyuum had expected that he would die in the mission and so this was part of his sentence. He was assisted by Rtas 'Vadumee, Special Operations Sangheili, and Special Operations Unggoy. The operation was even more complicated by the unexpected escape of the Flood from the facility. During the chaos that followed, the Heretic leader Sesa 'Refumee sealed himself in a protected zone of the station, to protect himself from the storm. The Arbiter drove the Heretics out by cutting the cables from which the facility hung from a larger structure, causing the gas mine to fall. After he had severed the cables, he chased the heretic leader in a Banshee to another part of the station. After crashing his Banshee, the Arbiter fought his way through massive amounts of Flood and a few surviving Heretics toward the station's hangar. Before Sesa 'Refumee could escape in a Seraph, the Arbiter assassinated him, but not before the Heretic Leader revealed the source of his heresy. The Arbiter was shocked to discover that the Heretics had been aided by the Monitor 343 Guilty Spark, a holy Oracle in the Covenant religion.

With the uprising suppressed, the Jiralhanae Chieftain Tartarus extracted the Arbiter and used the Fist of Rukt to capture the Oracle. His actions, which involved throwing the Oracle into the Phantom recklessly, angered the Arbiter enough for him to remind the Chieftain who he was dealing with. With Tartarus, he left the gas mine via Phantom, as High Charity and the fleet were leaving Threshold's system.

Battle of the Quarantine Zone
"We shall cut into the heart of this infestation, retrieve the Icon, and burn any Flood that stand in our way!"

- Rtas 'Vadumee

The High Prophets, though surprised by the fact that 'Vadamee had escaped alive from the gas mine, were not ones to waste such an outstanding warrior, and thus, 'Vadamee was sent to the "Quarantine Zone" on Installation 05 to retrieve the "Sacred Icon", which was needed to activate Delta Halo. Before the mission, Thel 'Vadamee witnessed the replacement of the Sangheili Honor Guards with Jiralhanae Honor Guards. Though distressed by change, and voicing his concerns politely to the Prophet of Truth, 'Vadamee made no further comment. Fighting his way through the Sentinel Wall (with a few surviving Unggoy and Kig-Yar) to deactivate the Library's shield, he made his way on foot to the Library, aided by the Spec Ops forces of Rtas 'Vadumee. Eventually reaching a gondola, he and the commandos made their way to the library with relative ease, though they were forced to relentlessly fend off Flood, controlled-armor resistance, and Forerunner constructs. The commandos chose not to accompany 'Vadamee to the "Icon," instead protecting their gondola, believing it to be their only way of escape despite the fact that Tartarus' Phantom was still present at the time.

The Arbiter proceeded into the Library, encountering the remains from a battle between UNSC Marines, Sentinels and Flood Combat Form, and witnessed Lieutenant Commander Miranda Keyes and Sergeant Johnson retrieving the Index. Using his armor's Active camouflage, he approached Johnson and Keyes. Attacking while cloaked, 'Vadamee surprised Johnson, knocking him unconscious with a headbutt. Keyes, reacting quickly, opened fire on 'Vadamee with her SMG's, dropping his shields and hitting him in the side, but the Arbiter soon disarmed Keyes as well, before Tartarus and his Jiralhanae joined the fight. After the initial scrape, Tartarus captured Keyes by using the Fist of Rukt's gravity manipulation to levitate her body and render her helpless, and claimed the Index for himself. A smug Tartarus informed the wounded Arbiter about the Jiralhanae' intended genocide of the Sangheili, and that those orders came directly from the High Prophets. A shocked 'Vadamee realized that he had been betrayed seconds before he was blasted into a massive shaft leading to the depths of Installation 05 with a shockwave from the Fist of Rukt.

Control room of Installation 05
"This one is but flesh and faith, and is the more deluded."

- The Gravemind describing Thel 'Vadam

Instead of being killed by the fall, as expected, the Arbiter was captured in mid-air by the Gravemind, the central intelligence of the Flood, and brought to its underground lair. It was here that the Arbiter met John-117, who had also been captured/saved by the Gravemind. The Gravemind tried to convince 'Vadamee that the Halos were weapons of destruction, not transcendence, which John-117 supported, saying the High Prophets were "making a big mistake." Though 'Vadamee was still in doubt, he was slowly beginning to believe. In order to "show the truth" to 'Vadamee, the Gravemind teleported him to the Control Room, while the Chief was sent to High Charity in order to stop the Index from activating Halo.

Discovering the consequences of the San 'Shyuum' betrayal of the Sangheili and the slaughtering of his species by the Jiralhanae, the Arbiter joined forces with a band of Special Operations Commandos, Minors, Majors, and a Zealot, as well as a small number of Unggoy, to raze a Jiralhanae encampment. Eventually, he met Rtas 'Vadumee yet again, joining forces to reach a Scarab. Near the Scarab, the Arbiter and his forces managed to save a group of captured Sangheili Councilors, and a group of UNSC Marines, including Sergeant Johnson.

Johnson made a shaky truce with the Arbiter in order to prevent Tartarus from activating Halo. Given they share a common enemy, they both agreed that Tartarus had to be stopped, with Johnson driving a captured Scarab and the Arbiter covering him from enemy Wraiths, Spectres, and Banshees from the air. After destroying many enemy units along the way, they successfully reached the Control Room of Installation 05.

Battle with Tartarus
"Tartarus, the Prophets have betrayed us."

- Thel 'Vadamee's last attempt to convince the Jiralhanae of the truth

'Vadamee fought several Jiralhanae Honor Guards before facing Tartarus, who was forcing Miranda Keyes to activate Installation 05. He was surprised to see the Arbiter still alive and there was a standoff between the two parties. The Arbiter asked 343 Guilty Spark, who was also present, what Halo's true purpose was. The Monitor replied that the Halos were built "to destroy all sentient life in the galaxy" so that the Flood would die of starvation. In addition, the ones who built the rings, the Forerunners, died upon firing the rings as planned, contradicting the belief of their "transcendence." This convinced the Arbiter of the truth that he had been repeatedly told. It was from that moment that 'Vadamee's faith in the Great Journey had been shattered, his alliance with the humans absolute, and the treachery of the High Prophets fully realized.

With this revelation, the Arbiter tried to convince Tartarus to turn against the San 'Shyuum. Tartarus, however, blinded by his fanatical belief in the Great Journey, as well as his hatred for the Sangheili, ultimately chose to side with the San 'Shyuum. In the battle that followed, the Installation was activated and threatened to destroy all sentient life in the galaxy. The Arbiter, with the aid of Johnson and several Sangheili, slew Tartarus, allowing Miranda Keyes to stop the activation in time. The shutdown, however, activated a fail safe system; the rest of the Halos were set to standby mode, and could only be activated remotely from Installation 00. 'Vadamee then escaped the Flood-infested installation with the surviving Humans and Sangheili forces.

Meeting the Chief on Earth
"Were it so easy."

- Thel 'Vadam

After Tartarus' defeat on Delta Halo, 'Vadamee officially changed his surname to "'Vadam," symbolizing his resignation from the Covenant; the rest of the Sangheili followed suit.

Upon arriving on Earth with Johnson, 'Vadam and several of his allies discovered the Master Chief, who had just "arrived" on Earth as well. When the Master Chief regained consciousness from his long fall, he attempted to kill 'Vadam with Johnson's M6 Series Magnum, but was stopped by Johnson, who explained to the Chief that the Arbiter and his kind have allied with Humanity. The Chief reluctantly backed down, although he at first did not trust Thel, 'Vadam assisted the Master Chief through the jungles near Mount Kilimanjaro, guiding him through the dense forest to the dam site where they were extracted. He then aided the Chief and the other UNSC forces during the defense of a UNSC base, Crow's Nest, from Covenant Loyalist invaders.

Battle of Voi
"Quickly! Let us find their ship. Make short work of this abomination!"

- The Arbiter in Floodgate

After leaving the Master Chief on the last departing flight from Crow's Nest before the base was leveled, Thel 'Vadam (known to his human allies only by his standing as the Arbiter) rejoined him at the docks, shortly after the Chief cleared the road to Voi of Covenant Loyalists and began to destroy a section of the Covenant mechanized presence defending the area rimming the Forerunner artifact. The Arbiter assisted the Chief and surviving UNSC forces in destroying a crucial anti-aircraft battery, aiding them as they fought through Covenant occupied warehouses, eventually helping them destroy the emplacement and opening a hole in the Covenant anti-air defenses to allow Lord Hood's naval forces to assault the Prophet of Truth's Forerunner Dreadnought, which was docked and idle atop the Artifact.

The strike upon the Dreadnought did no visible damage. An enormous, fiery blue sphere was triggered over the activated Artifact, and formed a portal through which Truth and the Covenant fleet retreated. 'Vadam roared in fury at the loss of their quarry. But before Lord Hood could consolidate the scattered and confused human resistance, a Flood-infested Covenant cruiser, which had broken through the Sangheili's quarantine fleet around High Charity, transitioned out of Slipspace nearby, crashing into the city and infesting a significant area in and around Voi.

The Arbiter and Chief proceeded to cauterize the local area of the Flood infestation, battling their way to the cruiser with the purpose of catastrophically overloading the crashed ship's engines to level the entire city before the parasitic infestation grew beyond control. They were aided by a handful of Marines who were not claimed by the Flood, and eventually Sangheili Special Operations shock troops, led by the recently promoted Ship Master Rtas 'Vadum, and a battle group under his command. 'Vadam learned of the fall of High Charity from a Sangheili Major who was leading Spec-Ops soldiers to fight alongside the Chief. The Arbiter assisted the Chief in clearing a swath to the crashed cruiser, and the Chief infiltrated the cruiser alone. He managed to recover a holo-projector that contained a fragmented message of Cortana. Rtas 'Vadum's fleet glassed the infected parts of Africa to prevent the Flood from continuing their infestation.

Battle of the Ark
"The Prophet will die by my hands - not theirs!"

- The Arbiter, in the level The Covenant



After the UNSC and Separatist forces regrouped, they learned from Cortana's message that the Flood had taken control of High Charity and were on their way to Earth. However, she continued to say that the Gravemind was unaware of the Portal, and states that on the other side is a solution to stop the Flood, without firing the remaining Halo rings. Because the Chief trusted Cortana, he and the Separatists dedicated all their forces to go through the Portal, arriving at the Ark. The Arbiter joined the Master Chief at the entrance of a local Silent Cartographer facility to clear their way through the building to the Cartographer terminal. Once there, they learned Truth's perilous location, as well as an unfortunate defense he had conjured from the Ark itself. When the group was attacked after activating the Cartographer, the Arbiter joined the battle for the skies, instructing the Chief to follow 343 Guilty Spark to a location for extraction.



With the decimation of the Covenant Loyalist Fleet, Rtas 'Vadum's carrier positioned itself near the Ark's Citadel - where Truth planned to remotely activate the rings - in preparation to deal a lethal blow to Truth's stronghold. Commander Keyes led a three-pronged assault, which the Arbiter and Chief participated in, on the shield generators to lower the barrier around Truth and the Citadel by deactivating the generator from a console in the tower's spire. After Sergeant Major Johnson failed to deactivate the third generator because of Jiralhanae resistance, the Arbiter landed his forces at the third tower along with the Chief to deactivate the final generator and shut down the barrier.

As Rtas 'Vadum maneuvered over the Citadel to glass Truth, High Charity exited Slipspace, crashing into the Ark. In its plummet to the surface, High Charity scattered a barrage of infection capsules which put 'Vadum's carrier out of commission and seeded the Ark with Flood. The Arbiter led his forces in conjunction with the Marines to clear the third tower of Flood, with the Chief's assistance. As a security measure, the Arbiter escorted a distressed 343 Guilty Spark to reconnoiter the damage inflicted to the Ark by the Flood, leaving his Sangheili with the Chief to push on to the Citadel.

Death of Truth
"I am Truth! The voice of the Covenant!"

- the Prophet of Truth

"And so you must be silenced."

- 'Vadam

After Thel entered the Citadel, joining the Chief at the bridge to the Citadel with a distraught 343 Guilty Spark, the Flood formed an alliance with them to reach Truth and abort the firing of the Halo Array. Fighting through the Loyalist forces standing between Truth and themselves, the Arbiter and the Master Chief succeeded in reaching the same platform as the Prophet of Truth. The Arbiter approached Truth, who was by this point partially infected by the Flood. The Gravemind spoke through Truth, informing him that he was deluded in thinking that he would become a god. 'Vadam warned the Flood mind to not infect Truth, stating, "I will have my revenge on a Prophet, not a plague!" Thel held Truth by the neck, and forced him to watch helplessly as the Master Chief deactivated the Halo Rings. 'Vadam then took his revenge by executing Truth with his Energy Sword. It is at this point that John-117 appears to begin to trust Thel more, having witnessed the death of the Hierarch who called for Humanity's destruction. John and Thel then faced the betrayal of the Flood's allegiance with the abortion of Halo's firing.

Destroying the Flood
"This is our fight, and I will see it finished."

- Thel 'Vadam to his fellow Sangheili

Fighting their way back the way they had come, the two witnessed the construction of a new Installation 04, and planned to activate it. The Arbiter, Johnson and Rtas 'Vadum evacuated all UNSC and Separatist forces from the Ark. The Arbiter, worried about the Chief (who went to High Charity alone to rescue Cortana) arrived after the Master Chief at High Charity's crash site, and eventually found the Chief, who had already accomplished his objective. 'Vadam used a Flamethrower to cover their escape as High Charity began to explode.

The two then escaped on a D77H-TCI Pelican from High Charity, crashing it into the newly constructed Halo; after fighting through numerous Flood forms, they met up with Sergeant Major Johnson and 343 Guilty Spark at the Control Room. The Monitor turned on them after realizing that an immediate activation of the ring would destroy it and damage the Ark, as the ring was not yet complete. In the battle that followed, the rampant Monitor killed Johnson and blasted the Arbiter out of the room; however, eventually 343 Guilty Spark was defeated by the Master Chief. Both Cortana and Thel expressed sorrow over Johnson's death. The Master Chief activated Halo and retrieved Cortana as the ring began to collapse. He and the Arbiter then retrieved Johnson's Warthog, crossed newly-built Forerunner structures as they collapsed, all while being attacked by more Flood and the now-hostile Sentinels. They succeeded in reaching the Forward Unto Dawn and escaped the Ark and Halo just in time. Upon entering the ship's cargo bay, it tilted and sent a M808B Main Battle Tank hurtling towards 'Vadam, nearly crushing him. 'Vadam ran into an alcove and narrowly dodged the tank. Before running to the bridge, he and the Chief (in a brief moment of camaraderie) exchanged nods; this was the last time 'Vadam saw the Chief. Soon after, Cortana activated the ship, as 'Vadam made it to the bridge and took control.

Return to Earth
"I remember how this war started. What your kind did to mine... I can't forgive you... but, you have my thanks, for standing by him to the end. Hard to believe he's dead..."

- Lord Hood

"Were it so easy."

- Thel 'Vadam

The portal collapsed as the Forward Unto Dawn was transiting and the aft end of the ship, with John-117 and Cortana, was sheared off and failed to return to Earth. The bow section, containing 'Vadam, made it through and crashed into the sea, where he was rescued. 'Vadam was present at the dedication of the memorial to those lost during the war, on March 3, 2553. After being thanked by Admiral Lord Terrence Hood for "standing by him to the end," saying "It's hard to believe he's dead," 'Vadam responded with "Were it so easy." This echoes his first line in Halo 3, symbolizing respect and similarity between a Spartan and the Arbiter, by how they are nearly impossible to kill. The Arbiter departed for Sanghelios aboard the Shadow of Intent as the ship master, with Rtas 'Vadum and the rest of the Sangheili who fought at the Ark to see if it was safe.

Sanghelios
During the aftermath of the Human-Covenant War, Thel 'Vadam continues to campaign with his fellow Sangheili for an indefinite peace with humanity. This has resulted in many Sangheili rallying in opposition, mainly the Servants of the Abiding Truth, an old orthodox society who continue to deify the Forerunners. Shortly after a Jiralhanae uprising in the state of Ontom, Avu Med 'Telcam, leader of the Servants, decided that the time had come to attack 'Vadam and oust him from the mantle of Arbiter. 'Telcam's forces besieged those of the Arbiter at Vadam Keep, but were forced into a stalemate due to fewer keeps joining the uprising than the Servants had expected. However, when Thel 'Vadam permitted Kilo-Five to deploy onto Sanghelios to search for Evan Phillips in the Temple of Abiding Truth, many Sangheili viewed this as sacrilege, joining 'Telcam's resistance. Thel 'Vadam's forces quickly began to lose ground to the Servants of Abiding Truth, they were quickly surrounded at Vadam Keep and outnumbered. As the Servants began assaulting the Keep, the battle was all but decided. In the final moments both sides were bewildered as a gargantuan human warship, the, made its debut and entered into position around Sanghelios. Admiral Hood personally offered to assist 'Vadam in the defense of his keep. While he wished to refuse such charity, he knew it would mean defeat, and thus he accepted. The UNSC Infinity proceeded to destroy one of 'Telcam's ships, Defender of Faith, and then utilized its Magnetic Accelerator Cannon batteries to destroy the resistance forces from orbit. 'Telcam escaped to New Llanelli due to a rescue by Kilo-Five, and three of his four frigates escaped the Arbiter's cruisers, which were destroyed by, disguised as a Kig-Yar vessel. This was to balance the strength of the warring factions.

Battle on Ealen IV
"The Arbiter. Maybe more than any other figure, a symbol of what the galaxy could one day become."

- Admiral Lord Terrence Hood

Due to an escalation in Jiralhanae raiding parties against the Sangheili throughout joint-occupational zones, Thel 'Vadam accepted Lord Hood's request to have a peace conference on Ealen IV with a Jiralhanae Chieftain named Lydus, in order to gain access to the Jiralhanae resources. Upon meeting Lord Hood, Captain Lasky, Sarah Palmer, and two other Spartan Fireteams on the planet's surface, the three parties then engaged in the conference. During the conference, Thel appealed to Lydus' care for his own race, explaining that the Jiralhanae will eventually turn against each other once there are no other worlds to plunder.

The meeting was soon ambushed by the Covenant Remnant trying to stop the negotiations that were taking place. Surprised by the ambush, Lydus believed that he was deceived by Thel 'Vadam, but Thel quickly reassured him that the Covenant attacking them are not his own troops by saving Lydus' life from the sights of a Kig-Yar sniper. As more of Covenant Remnant troops begin to invade, the three conference parties began to make their way to a human shuttle, only to have it destroyed by Banshees. Commander Palmer shielded Thel with her body from the resulting explosion. With all communications blocked, and no way to contact Infinity for reinforcements, Lasky, Palmer, Lord Hood, the two Spartan Fireteams, and the delegates made their way to a parts depot and sealed themselves inside.



While all three factions were trapped in a plasma refinement facility, Thel 'Vadam worked out a plan with Lord Hood and Lasky as to how they were going to restore communications, and where they were going to find a more decent shelter. Thel attempted to include Lydus in the planning, only to be accused of working with the Covenant Remnant, an accusation that he quickly rebuffed. When Lasky found a suitable redoubt for the group to stay, he decided to break off from the group with Spartan Naiya Ray in order to find a way to restore communications.

As Thel, the remaining Spartans, Hood, and the Jiralhanae began to make their way to the redoubt, Palmer asked Thel if he thought the Covenant Remnant knew about their path through the underground to the redoubt. He responded that it was very likely. Upon hearing this, Palmer sent the Fireteams out to clear the way. Thel and Lydus insisted on taking part, claiming they were warriors first and diplomats second. However, Palmer convinced them both to leave the fighting to the Spartans, as they were both sent to the planet as peaceful ambassadors.

It was not long before the group was confronted by a Lich. The Lich and its troops were quickly destroyed through the swift actions of Palmer. She ordered the Fireteam Jackknife to move onward to the redoubt, while Hood searched the dead enemies for information. Once the dead soldiers were properly inspected, the three factions continued their journey towards the enemy fortified redoubt. Along this route, Lydus demanded that Thel explain how the Jiralhanae can trust the Sangheili if Thel is not able to ensure a peaceful summit.



Inside the redoubt, Lydus was still unconvinced of Thel and Hood's concern for the Jiralhanae race, accusing both of playing kingmaker. During this conversation, the leader of Fireteam Jackknife, Vladimir Scruggs, flanked Hood and held him at gun point. As Palmer demanded to know what Scruggs was doing, Lydus began to threaten the traitourous Spartan. Holding out a hand to stop the Chieftan from charging, Thel asked Scruggs for his motives. Scruggs responded that the list is long and explained to Palmer that there are multiple levels of politics that have lead to this point. In particular he pointed out how strange it was that Thel had not been able to achieve stability within the Sangheili on his own over the past five years, hinting at some foul play within the politics.

In the midst of the explanation, Palmer shot Hood in the outer-thigh, causing the Admiral to drop and providing her the opening to attack and eliminate Scruggs. After Hood is bandaged, Thel assisted him on the walk down stairs to a small Covenant tug ship. The ambassadors and Palmer escaped on this ship, with DeMarco and Fireteam Bailey giving their lives to provide anti-aircraft covering fire. Thel, Lydus, and Hood all parted ways, not having reached an agreement.

Guardian Awakening
Thel would eventually return to Sanghelios. Here he would be contacted by the UNSC for assistance in finding a Forerunner construct called a Guardian. He agreed and met with Jameson Locke, Commander Sarah Palmer, and Doctor Catherine Halsey.

The Arbiter was originally angered to find that Locke was leading the UNSC Fireteam. During the Human-Covenant war, Locke had been a member of ONI, recommending they assassinate Thel, and had volunteered to carry out the mission. Thel refused to allow the SPARTANS to access Sunaion until his forces were ready to assault the Covenant forces.

Battle of Sunaion
He would lead his Swords of Sanghelios and Fireteam Osiris to fight the at Sunaion.

Combat
"Parasite! Rise up and I shall kill you -- again and again!"

- Thel 'Vadam to the Flood

Thel 'Vadam stands an intimidating seven feet and ten inches, and possesses huge fingers, as do all other Sangheili. Because of this, Thel struggles to put his hands around guns such as Magnums or Plasma Pistols (and due to his height, when sitting in a Pelican Dropship, he involuntarily takes up a lot of leg room). In Halo 2, numerous small graphical and gameplay differences exist between the Arbiter and the Master Chief. When playing as the Arbiter, the Chief's flashlight is replaced by an Active camouflage feature, exclusive to Halo 2; due to the antiquated armor of the Arbiter, the camouflage does not last forever—it lasts for ten seconds on Easy and Normal difficulties, and five seconds on Heroic and Legendary difficulties. The Arbiter bleeds purple blood instead of red, and his Heads-up display is sleeker. The Arbiter's HUD is also a purple color, rather than the Spartan blue; in Halo 3 it is teal and is presented in a more curved fashion than Player One's. Player Three and Four's HUDs are also more curved as they too are Sangheili. In Halo 2, the sound his shield makes when it is depleted is different from that of the Master Chief's. In Halo 3, he still has Active camouflage, but it is only illustrated in the first cutscene of the game and to elude enemies—it cannot be used when playing as the Arbiter unless you pick up the Active camouflage. He has a flashlight on his left shoulder in Halo 3, which can be used by players in Cooperative Play.

The Arbiter is very experienced at combat and has extensive knowledge of every weapon and vehicle. The Arbiter expressed a desire to understand human weapons even before his alliance with the UNSC. His most commonly used weapons are the Plasma Rifle, Energy Sword, and the Carbine.

In Halo 3, the Arbiter is a very useful ally against the Flood when he has his Energy Sword out, but when fighting Covenant forces on his own on Heroic and Legendary, the NPC Arbiter tends to be knocked out frequently, for long periods of time, especially on Legendary. This is mostly due to his tendency to lead suicidal charges with his Energy Sword, despite the enemy's great distance from him. However, he is useful on Normal and Easy. Also note that when given a Missile Pod (using the support weapon glitch, or putting it by his unconscious body) the missiles will lock onto enemy NPCs.

Personality
Thel, like all Sangheili, is keen to do things in an honorable manner, though he is more flexible when it comes to equipment, weapons, and vehicles. His hatred of the Jiralhanae doesn't seem to be as strong or destructive as that of other Sangheili; one example of this is when the Arbiter tried to reason with Tartarus in Installation 05's Control Room. He is shown to be true to his title "Arbiter" as he often tries to negotiate with some of his other enemies (Yanme'e, for example) and will only kill when forced to do so. He has deep respect for his fellow Sangheili and a grudging respect for the humans, specifically John-117 and Sergeant Johnson.

Despite being a former enemy of humanity, Thel has shown a willingness to fight alongside them toward a common goal. Even before peace was established, Thel was willing to work with Avery Johnson to stop Tartarus. Johnson's aid in the fight with Tartarus and the fight he put against him earlier may have earned Vadam's respect as he seemed to respect Johnson in their later encounters. He also showed sorrow at Johnson's death, and said that even beyond death, the Sergeant still guided them. He was also willing to fight side by side and back to back with the Master Chief, someone he once considered a great enemy. Thel also respected humanity enough to be present at a memorial to everyone who fell in the war. While he respected the humans he was wary of their intent and likely had his own reason for having Evan Phillips visiting Sanghelios.

Although he often conducted himself with honour and a measure of tolerance towards others, he was not beyond pride and impatience, and would sometimes act dismissively or condescendingly to people like Catherine Halsey or Spartan Locke. Those who did not know him well frequently thought him stubborn and willful.

Trivia

 * Thel's weapons of choice in Halo 3 seem to be the Energy Sword and the Plasma Rifle, but he also uses the Covenant Carbine and the Plasma Pistol.
 * Thel's personal blade is named "Prophets' Bane" after he slayed the Prophet of Truth with it.
 * Thel 'Vadam is the only known Sangheili witnessed to be branded with the Mark of Shame.
 * Thel 'Vadam wears silver armor without mandible guards in Halo 2. In Halo 3, he wears bronze armor with mandible guards.
 * After returning to Sanghelios after the Battle of Earth, Thel has taken to donning a bespoke ceremonial battledress that both pays homage to the Arbiters of the past and represents a transition forward towards his vision of a united Sanghelios.
 * One of the Sangheili honorific beliefs is that only those with honor should deserve something as prestigious as a name. Thus, after his trial, his name and honor were stripped by the San 'Shyuum before the Sangheili left the Covenant, which is why he was only ever referred to as "the Arbiter" throughout Halo 2. With the outbreak of the Great Schism, Thel regained his name.
 * Thel 'Vadam is voiced by actor Keith David.
 * In the final level of Halo 2, The Great Journey, at the point where Sergeant Johnson takes over the Scarab, the Marines refer to the Arbiter as they would John-117. This is an error in which they react to the player character as their ally (which, up until that point, is John-117).
 * Thel 'Vadam is included in MSNBC's list of the "Top 5 Best Aliens in Video Games."
 * When the Arbiter activates his active camouflage in Halo 2, his eyes will remain visible. This is only noticeable in co-op.
 * In Halo 2, if you man the turret at the beginning of the level "The Arbiter" and look all the way to the left, you can see a Sangheili skull on 'Vadam's right shoulder.
 * The original title for the character was "The Dervish," a title from the Sufi Sect of Islam, but was changed to avoid overt parallels with the Muslim world.
 * Thel 'Vadam was the first member of the Vadam family to exceed the rank of Shipmaster.

Appearances

 * Halo 2
 * Halo 2: Anniversary
 * Terminals
 * Halo 3
 * Halo: First Strike
 * Halo: Ghosts of Onyx
 * Halo: The Cole Protocol
 * Halo: Evolutions - Essential Tales of the Halo Universe
 * The Return
 * From the Office of Dr. William Arthur Iqbal
 * Halo Graphic Novel
 * Halo Legends
 * Origins
 * Halo: Glasslands
 * Halo: The Thursday War
 * Halo: Escalation
 * Halo: Broken Circle
 * Halo: Hunters in the Dark
 * Halo 5: Guardians