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Victory comes on the wings of death.
Reports of the one they call Bracus Tho'ourg began in the earliest days of contact with the Cabal. The first Guardians who faced him are long lost, but the legends speak of a powerful commander who secured the Buried City with merely a fraction of the Cabal's forces on Mars. If these reports are accurate, they provide clues not only to Tho'ourg's tactical prowess but to the Cabal lifespan.
Embrace suffering. Only then can it be conquered.
Bracus Tha'aurn appears remarkable among Cabal commanders for his interest in the glories of our Golden Age. Having been faced only in the company of Psions, the Vanguard has reason to believe he maintains some sort of command over their deployment.
If your enemy speaks with a blade, master the sword.
No one knows what fascination the Vex hold for the leader of the Blind Legion, but Primus Sha'aull has put his command at great risk by pushing into lands occupied by the machines.
The Psion Flayers
Somewhere among their forces, the Cabal hide one of their most powerful weapons, the Psion Flayers. The extent of their ability is still uncharted, but Cryptarch studies and Warlock fears have led the Vanguard to classify them as a serious threat. Many among the Warlock orders believe the Flayers pulled Phobos from its natural orbit, holding it in place, waiting for the order to release as a weapon.
"The last sounds to reach their ears were the creak of tank tread and the battle-cry of Ta'aurc."
From his armored seat of power, Valus Ta'aurc has claimed more ground on Mars than any known Cabal commander. His name is feared throughout Meridian Bay, and the tread-marks left by his tank have come to signify the expansion of the Cabal's ever-widening Exclusion Zone.
"Enter as soldier, survive on the crushed ambitions of lesser warriors."
Aru'un's ascension to Val will never be considered official by the Cabal High Command proper, but in the Prison of Elders the approval of the outside world is meaningless. To his fellow prisoners, Aru'un is a Val worthy of following.
Valus Trau'ug retains the title of Valus only in defiance to his ex-allies and commanders in Cabal high command.
When the Cabal high command ignored his pleas to advance on the Reef, he viewed their inaction as weakness. The most loyal members of his legion pledged their fealty and Trau'ug took to massacring his officers, marking himself and his soldiers as traitors of the Empire.
Trau'ug then set course for the Reef. How he and his army became denizens of the Prison of Elders is not public record, and Variks tends to skirt the issue when pressed. What is known, is that Trau'ug's bloodlust and mastery of wartime stratagem is intact within the prison.
Using battle-tested Cabal field techniques, the Broken Legion crush any who dare accept Trau'ug's challenge. His custom-rigged shield randomizer keeps attackers off guard as he presses every advantage.
Martian battlefield reports note that Valus Tlu'urn's weapon of choice is a back-mounted Arc cannon. The device delivers a payload so powerful the Vanguard estimates Tlu'urn could face a Goliath Tank himself. The Valus carries recharging Arc cells that feed energy to the cannon, allowing him to siege enemy emplacements indefinitely.
Reports suggest he is commanded by Primus Ta'aun and shares battalion duties with Valus Mau'ual. Together, this Cabal triumvirate is responsible for the deaths of countless Guardians on the Martian battlefields.
Reports suggest Valus Mau'ual's armor allows him a degree of maneuverability unseen from other Cabal warriors. It features a never-before-seen propulsion system that improves on the Valus's already considerable striking ability.
Tales of his skill in hand-to-hand combat on the Martian frontlines claim he carries no firearm into battle, preferring instead to charge headlong like a nimble boulder.