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Facius (called Butch by Connor Brien) was a Jiralhanae stationed on the Covenant ship Valorous Salvation in 2552, with his brother Hammadus. Like Ceretus, Facius opposed Parabum taking over their pack. After Maladus tried and failed to defeat Parabum in combat, Facius became Ceretus' right hand.
The pack which crewed the Valorous Salvation was in fact the product of two separate packs which had recently been merged by the Covenant leadership. The two clans were ancient enemies that had fought even before the massive civil war that had knocked the Jiralhanae back to a pre-industrial state. Naturally led to tensions in the two factions with the pack. One clan, led by brothers Ceretus and Maladus, felt themselves to be the more intelligent faction of the pack, and their devout religious beliefs were more in line with those of the Prophets. The other faction, led by the pack's Chieftain Parabum, believed only in muscle and tradition, and used relics in more opportunistic and disrespectful ways.
During the Fall of Reach Parabum exhibited cowardice when he ordered the ship to retreat from the massive attack and instead landed on the nearby Beta Gabriel. When they first arrived on the planet they hunted the humans they found there and feasted like never before. As the number of humans dwindled they ate the Unggoy who had been aboard the ship, and Parabum instituted limits on hunting and eating the humans.
Shortly afterward Maladus snapped and challenged Parabum over his cowardice and abandonment of their duties to the Covenant. However, Parabum was stronger and mercilessly pummeled him into submission before tearing his throat out with his teeth. This only served to further enrage Ceretus.
After capturing Connor Brien and returning to their camp after Jiralhanae of Facius's hunting party killed one of the captives, Hague, for fun, however when Parabum's hunting party returned he was annoyed and embarrassed Ceretus in front of the others.
Ceretus then began plotting to overthrow Parabum, but he had no hope of beating the Chieftain in a direct challenge. Instead Ceretus tried to convince Hammadus, who was the only one strong enough to defeat Parabum. He did so by using Facius, and arguing that they needed to overthrow Parabum, return to the Covenant, and beg the gods for forgiveness or else face damnation.
Ceretus got Facius to try to convince Parabum to return to the Covenant, with Hammadus promising to protect his brother. When Facius spoke to Parabum however, the Chieftain responded by saying that there were no gods, causing Ceretus to erupt with pious indignation. Parabum then killed Ceretus with his gravity hammer. Connor Brien then shot Parabum and Hammadus with his tranquilizer gun, knocking them unconscious. Pandemonium reigned as the other Jiralhanae turned on each other. Facius was either killed in the chaos or else was killed by the UNSC reinforcements which landed on Beta Gabriel soon after and eliminated all of the Jiralhanae survivors.
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