Ussa 'Xellus

Ussa 'Xellus was a Sangheili rebellion leader who was opposed to the Writ of Union in the Covenant's early years. He was noted as a brilliant military strategist and was accompanied by his mate Sooln.

Military career
Ussa 'Xellus was born in the state of Xellus on Sanghelios. He served as a military commander for Sanghelios. During the Sangheili-San'Shyuum 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.

Rebellion against 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. He believed 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 volcano in the region and used their funds to purchase vehicles for the rebellion. Meanwhile, the Covenant sent out assassins and spys to track down 'Xellus.

Ussa and his mate, Sooln, travelled to the Sangheili mining colony of Creck in 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 'Crecka waiting for them at their ship at a spaceport. Although he was initially reluctant to trust 'Crecka, the elderly Sangheili convinced Ussa that he wished to serve with him and claimed to know of a Forerunner world, Shield World 0673, that Ussa and his insurgents could use as refuge. Intrigued, Ussa allowed 'Crecka to lead them to the shield world, where the three Sangheili entered its interior. After landing, they explored the world's artificial ecosystem until they encounter Shield World 0673's monitor, Enduring Bias. The monitor agreed to allow 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. He informed them that they were travelling to the shield world for refuge and ordered his followers to load the transport crafts with weapons, supplies, and eggs. As the group began to pack up, Vertikus, a known weapons dealer that aligned himself with Ussa, 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. However, Ernicka defended Ussa and disarmed the spy. Ussa attempted to order his followers to capture Vertikus for interrogation, but 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.

Personality and traits
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 was widely respected by his followers, and even those that opposed him. He cared greatly for the individuals among his clan and for those that served under him. He often helped females care for eggs—a sign of a great leader among Sangheili. 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.

List of appearances

 * Halo: Broken Circle