Abomination (Earth-5875)

"End this affront to our people! Slay the Abomination!"

- - Anonymous sangheili to Dahr 'Voliree

The "Abomination" was a xenomorph Aggressor born from the sangheili First Blade officer Kule Vars after being subjulgated by Specimen 6 during the Battle of Terra Nova. After its birth, the Abomination became free to slaughter the human Marines on Terra Nova, only to die at the hands of Vars' former war brother, Dahr 'Voliree.

Birth
"Weaken and then harvest the sangheili First Blade."

- - The Patriarch to Specimen 6 Following the xenomorph outbreak on the human colony Terra Nova and the intervention of the UNSC, sangheili of the Silent Shadow were sent to the colony in order to investigate the disapperance of a group of sangheili and unggoy of the Covenant Special Operations on the planet, only to discover it was a human world. One of the sangheili sent, First Blade Kule Vars, eventually fought against the xenomorph Aggressor Specimen 6 in an ancient forerunner arena on the planet. Vars was mortally wounded during the duel, and was impregnated by a Facehugger, which implanted a Chestburster on him. The Chestburster eventually hatched and grew to become the Abomination.

Free
"See the size of that thing?! What WAS that?"

- - Anonymous UNSC Marine of the 1st Battalion, 3rd Regiment

Once it fully matured, the Abomination started killing all of the UNSC Marines of the 1st Battalion, 3rd Regiment which had arrived on Terra Nova, collecting their heads as trophies. Its violence and rampage took the attention of Dahr 'Voliree, another First Blade and former partner of Vars.

After sighting the Abomination, 'Voliree notified his Special Operations Commander about its existence. After 'Voliree recovered all missing Covenant technology on the planet, he was ordered to locate and kill the Abomination at all costs, calling it an affront to their species.

Death
Hours later, the Abomination came face-to-face with Voliree inside the forerunner structure beneath the surface of Terra Nova, which was flooded with lava. In the ensuing violent duel, 'Voliree was able to kill the Abomination with his Type-1 energy sword, dragging its body to the roof of the ONI research facility above the forerunner site and roaring as he emerged victorious.