Ussa 'Xellus

"We acted as such because the Sangheili must not surrender to the San'Shyuum—and the Covenant is based on foolishness. The Great Journey. Where is your proof of this Journey, for anyone but the Forerunners? We hold these relics to be precious and sacred, but we use them ourselves in this very world. It is the freedom, the independence of our people that we fight for, Mken!"

- Ussa 'Xellus, to Mken 'Scre'ah'ben on his reasons for rebelling

Ussa 'Xellus was a Sangheili commander and Kaidon of Xellus who was opposed to the Writ of Union in the Covenant's early years. He was noted as a brilliant military strategist and founded the Ussans of the Refuge.

Military career
Ussa 'Xellus was born in the state of Xellus on Sanghelios. He served as a military commander for Sanghelios. During the San'Shyuum-Sangheili War, he fought against the San'Shyuum in numerous battles serving as a field commander. He led Sangheili forces in a skirmish on the Planet of Blue and Red in 860 BCE, along with his second-in-command Ernicka the Scar-Maker. When he first arrived on the planet, he completely reorganized its defenses. During the battle, he was observed by High Lord of Sacred Relics, Mken 'Scre'ah'ben. Mken had 'Xellus marked for assassination, but realized that if the San'Shyuum were to capture and interrogate Ussa, they could learn more about the Sangheili and possibly have him convince the Sangheili to surrender. Instead, Mken hoped to find Ussa useful in the future and belayed the order. Ussa later led Sangheili assault teams that were approaching the San'Shyuum scientists and warriors. Mken deployed Aggressor Sentinels to weaken the Sangheili's attacking army, but Ussa survived. After Sangheili assassins forced Mken and other San'Shyuum to retreat to the planet's orbit, Ussa regrouped with his attack force. Ernicka did not believe the San'Shyuum would attack from orbit, since the San'Shyuum were not willing to risk causing damage to the planet's Forerunner structures. However, Ussa realized that the San'Shyuum were intending to use a weapon from their Forerunner Dreadnought that was too weak to damage the structures and kill all exposed Sangheili. Ussa ordered for all the Sangheili to retreat into the interiors of the structures to survive the orbital attacks.

As the San'Shyuum orbitally bombarded the planet, Mken knew that Ussa was wise enough to survive the attack. Mken was discreetly glad that 'Xellus had survived the battle as he saw potential in the Sangheili commander. Mken predicted that he would encounter Ussa again. He eventually managed to escape the world and would later engage in many more battles in the war. His first-born son, Ossis 'Xellus, died in battle presumably during the war.

Rebellion against the Covenant
"This Great Journey—what is it? Just another surrender, from what I can tell! Did the Forerunners truly summon us to sublimation, in the shadow of these Rings? Or is that an excuse on the part of the San'Shyuum to exterminate us? It is a murky pond in which no Sangheili would dare bathe!"

- Ussa warning the Sangheili of Xellus to not trust the Covenant

When the war ended in 852 BCE, Ussa was opposed to the unification of the Sangheili and San'Shyuum to form the Covenant, believing that the Sangheili were surrendering themselves to the San'Shyuum. In 851 BCE, 'Xellus warned the residents of Xellus to not trust the Covenant or the San'Shyuum. Some of the keep's residents did not agree with Ussa and reported his heresy to Covenant authorities. In response, attack fighters were sent by the Covenant to fire upon Xellus keep. The fighters dropped explosive charges on the keep's plaza, instantly killing numerous Sangheili. During the assault, Ussa succeeded in destroying one of the crafts. Ultimately, the keep was destroyed and hundreds of the keep's inhabitants were killed. However, the survivors were led by Ussa and they fled to the region of Nwari at Sanghelios' southern pole. Ussa and his followers hid within a dormant volcano in the region and used their clan's funds to purchase vehicles for the rebellion. Meanwhile, the Sangheili treaty commission sent out assassins to locate Ussa.

Ussa and his mate, Sooln, travelled to the Sangheili mining colony of Creck on Ussa's personal vessel, Clan's Blade, to recruit followers into their insurgency, disguised as engineers. Ussa's informant on Creck, Muskem, died after he allegedly fell into a boiling pit of magma by accident. After several failed recruitment attempts at the planet's mines, Ussa and Sooln encountered the elderly 'Crecka waiting for them at their ship at a spaceport. Although he was initially reluctant to trust 'Crecka, the Sangheili revealed that he knew of a Forerunner world, Shield World 0673, that Ussa and his insurgents could use as refuge. Intrigued, Ussa had 'Crecka lead them to the shield world, where the three Sangheili entered its interior. After landing, they explored the world's artificial ecosystem until they encountered the shield world's monitor, Enduring Bias. The monitor allowed the Sangheili to live on the world in refuge, as long as they informed it of their intentions. The Sangheili were able to convince the monitor and Ussa returned to Nwari, Sanghelios to transport the rest of his allies to the shield world.

Back in Nwari, Ussa's allies eagerly awaited his return. As Covenant assassins began to close in on Ussa's camp, he realized that there was likely a spy among his group. Without informing anyone else of his plan to detect the spy, Ussa delivered a speech to his followers informing them to prepare to leave for a new home of refuge. As the group began to pack up, Vertikus asked where they were going. Ussa avoided directly answering his question; he only told Vertikus that their new home was far from Sanghelios. Frustrated, Vertikus revealed himself as the spy and charged at Ussa with a burnblade. Ernicka defended Ussa and disarmed the spy. Although Ussa attempted to order his followers to capture Vertikus for interrogation, the spy was ripped apart by a mob of ten angry Sangheili before Ussa could finish giving out the command. Eventually, the Sangheili finished packing up and departed for the shield world.

Life on the Refuge
"Clansfolk! You have trusted me thus far! I have taken you from one world to another! You must trust me here—we have crossed the Great Torrent! We cannot turn back! I believe we are safe here—the Covenant does not know of this world! It is an uncharted place and they are not likely to find it! If they approach, we will have ample warning. We will survive! We have food, water, air, and most of all, hope! Rejoice with me in this...and remember that true Sangheili are always prepared for self-sacrifice! This is our keep now! Our home! Yes—and it is Sanghelios! Because wherever we go...there also is Sanghelios!"

- Ussa delivering a speech to the Ussans

As the Sangheili settled on the shield world, they began to call themselves the "Ussans" as they started to establish their colony and new home, now called the Refuge. In 850 BCE, Ussa and Ernicka were approached by Salus 'Crolon who openly expressed his doubts about Ussa's decision. Ussa dismissed 'Crolon's worries about angering the Forerunners by living on the shield world, and then addressed all Ussans in a speech to give them hope and reminded them that they had crossed the "Great Torrent". However, 'Crolon continued to express his doubts about Ussa to other Sangheili, such as Tersa 'Gunok, while away from Ussa, Ernicka, and Sooln. Later, while Sooln was conversing with Enduring Bias, the monitor revealed the shield world's Disassembler capabilities; the shield world was capable of breaking apart and imitating an explosion, while remaining habitable. Sooln reported her discovery to Ussa, which was promptly backed up by Bias. While the monitor was demonstrating the Disassembler process through holography, he confirmed that there was a 49% chance that the process would lead to the destruction of all organisms on the world. Although Ussa did not intend for other Sangheili to know about the Disassembler process, Bias carelessly revealed this information to Tersa.

Meanwhile, 'Crolon and 'Drem began to distrust Ussa and attempted to share their sentiments with the other Ussans. The two Sangheili later jumped to the conclusion that Ussa was conspiring with the San'Shyuum, due to several poorly worded, inadvertently incriminating conversations with Enduring Bias. Despite Tersa's attempts at ending the misconceptions, the duo began to plot a rebellion against Ussa. Tersa remained reluctant to inform Ussa or Ernicka of the situation, as he did not want to appear to be a "dishonorable informer". After Tersa and Lnur 'Mol spotted 'Crolon and 'Drem attempting to recruit Gmezza and Scorinn into their rebellion, 'Drem and 'Crolon attempted to convince Ussa that the former two Sangheili were plotting against him. Ernicka brought Tersa and Lnur to the Strategy Hall, where Ussa held court. At Tersa's request, Ussa had Enduring Bias, Gmezza, Scorinn, 'Crolon, and 'Drem all brought before the court. Although 'Crolon and 'Drem insisted that Tersa was spreading treason, Enduring Bias provided footage of the two plotting against Ussa. When Ussa ordered for Ernicka to arrest the two, 'Drem attempted to run but was quickly killed by Ernicka. As Ernicka led 'Crolon to the prison facilities, he reminded Tersa, Lnur, Gmezza, and Scorinn to trust him. After sending the four away, he continued to consult Bias about the Disassembler process.

The Rending
"We will be safe here. The true Sangheili will grow in numbers and in strength. We will learn how to harness the power of the Forerunners. And those who follow us will one day take Sanghelios back."

- Ussa 'Xellus, following the Rending

Some time later, Ussa was informed the 'Crolon had escaped. Ussa, Sooln, and Bias raced to the ship hangar and arrived just as 'Crolon left the planet in Clan's Blade. Although he did not believe that 'Crolon would return to the Covenant, he nonetheless began to prepare to activate the Disassembler process. Eventually, Clan's Blade was intercepted by Covenant patrols and 'Crolon offered to reveal the location of the Refuge in exchange for his life. For failing to kill Ussa at the Planet of Blue and Red, Mken 'Scre'ah'ben—now the Prophet of Inner Conviction—was sent by the Hierarchs to lead a fleet to quell Ussa's rebellion. When a Covenant fleet arrived over the shield world, Ussa intended to activate the Disassembler process but first decided to contact the fleet, hoping to possibly negotiate a deal. Mken's carrier sent a transmission that was picked up by Enduring Bias. Bias presented the transmission to Ussa, allowing the two to see and hear each other. Mken gave Ussa an offer: if Ussa and Sooln turned themselves in, the rest of the Ussans will be free to live on Sanghelios. Knowing that his people would still likely be killed, Ussa instead offered to hand over relics to the Covenant each solar cycle if the fleet withdrew. Mken told Ussa that the Covenant would not agree, and insisted that he surrendered for the sake of his people. Again, Ussa declined and told Bias to end the transmission. As the Covenant military invaded the shield world, Ussa sent one final transmission to Mken. He warned the San'Shyuum that he was about to destroy the shield world and suggested for the Covenant to extract their warriors off the world.

As the Covenant fleet retreated to the planet's orbit, Ussa and Enduring Bias activated the Disassembler process. The shield world was seemingly destroyed, along with all of its inhabitants. In truth, Ussa and his allies survived aboard large freight movers. Mken believed that he spotted the freighters within the debris of the Refuge, but chose to ignore as he knew Ussa would not present a threat to the Covenant. When the Covenant fleet left the system, Enduring Bias set the fragmented habitats within the system's asteroid belt. The Ussans continued to inhabit the habitable sections of the Refuge, as Ussa pledged to one day have his people take back Sanghelios. At some point, the Primary Section of the Refuge was struck by a comet and disabled Bias. Ussa would later write that he believed the monitor would repair himself and become active in the future.

Legacy
Before his death, Ussa documented the history of the Refuge and the Disassembler process. However, by 2552, the documents had become difficult to read due to the evolution of the Ussan language. At some point, statues of Ussa with Sooln were erected within the Hall of the Godminds in Section Five of the Refuge. A sculptural garden featured three-dimensional images of Ussa, including one that portrayed him protectively holding Sanghelios. Sculptures of Ussa's son and grandson, and Ussa's closest allies, were placed nearby. The Refuge, occasionally referred to as the Ussan colony, continued to be the home of the Ussans for over three thousand years. After the Rending, the Refuge's system was named the "Ussan system" by the Covenant and marked with a scarlet border—meaning forbidden by all. Ussa's rebellion was noted in the Notes on the History of the Covenant, written by Zo Resken—a descendant of Mken 'Scre'ah'ben. Resken learned of Ussa and his history by the writings of Mken, who wrote of Ussa's possible survival and the Forerunner shield world that may be within the system.

Ussa's descendants continued to hold the title of kaidon within the colony. By 2553, the colony was ruled by Kaidon Bal'Tol 'Xellus, who made contact with members of the recently dissolved Covenant-mainly Zo Resken and an accompanying group of survivors from the Fall of High Charity. The Ussans were allowed to return to Sanghelios if they pleased, while Sluggish Drifter repaired Enduring Bias. The monitor, believing it to be Ussa's intent, reconnected the surviving portions of the shield world and formed a small ringworld.

Personality and traits
"You have always found your own path, following your own heartfelt beliefs. You have fought bravely; you have evaded us with cunning, with forethought and wisdom. You have greatness! I wish we could have that same greatness within the Covenant. You are greater in your way, than any San'Shyuum I know."

- The Prophet of Inner Conviction, to Ussa

Ussa was an intelligent and highly innovative individual. In battle, he was considered strong, quick, and very experienced. High Lord Mken 'Scre'ah'ben, a San'Shyuum, believed that Ussa cast an aura of authority and sharp awareness on subordinates. Ussa did not believe in the Covenant religion or the Great Journey; he noted that Enduring Bias spoke without dignity and never acted "divine", which contrasted with the Covenant's religious views on Forerunner ancilla. Ussa was widely respected by his followers, and even those that opposed him. He cared greatly for the individuals among his clan and for those who served under him. After addressing his followers, he would sometimes descend and walk among them, symbolically aiding them in their work—such as helping females care for eggs—a sign of a great leader among Sangheili. Ussa was noted to be unusually merciful for a Sangheili. He tolerated Salus 'Crolon, despite his near-treasonous behavior, and Ussa later warned Mken to evacuate all of his troops off the shield world before he "destroyed" the planet.

Ussa cared deeply for his mate, Sooln 'Xellus. He enjoyed the way she expressed herself, stating that it was one of her qualities that he found endearing. Whenever Ussa had to go into battle, he would still often be thinking of Sooln. Ussa had great trust in Ernicka the Scar-Maker, his close friend and second-in-command. Ussa even allowed a Covenant spy to charge directly at him, knowing Ernicka would act and defend Ussa. Ussa and Ernicka were reluctant to trust Enduring Bias, but they knew it was necessary to survive on the Refuge and to remain hidden from the Covenant. Over time, Ussa and the monitor formed a rapport of sorts, as Bias began to adhere to Sangheili culture and customs.

List of appearances

 * Halo: Broken Circle