Abaddon
From Halopedia, the Halo wiki
The Organon was a rumored Precursor artifact of incredible power, believed by some Forerunners to be able to activate all Precursor artifacts. It was considered to be the most sought-after Precursor artifact by Forerunner archaeologists.[1]
In approximately 100,000 BCE, Bornstellar Makes Eternal Lasting sought the artifact on both Edom and Erde-Tyrene using a pair of human guides to lead him to its presumed resting place in the Djamonkin Crater.[2] Instead he found the Cryptum of the Didact, who outright denied the Organon's existence.[2]
Years later, the Flood revealed to the Librarian that the Organon was actually the Domain, which was a Precursor consciousness embedded within their ancient structures. Its takeover by the Flood allowed them to use Precursor artifacts as weapons, and so gain an edge over the Forerunners.
