The Cleansing Blade is a Sangheili paramilitary organization with roots that stretch into Sanghelios's ancient history, tracing back to a time before the formation of the Covenant Empire. An underground order of warriors, spies, and assassins, the Cleansing Blade's exploits were the subject of legends; its members targeted criminals, warlords, and keeps that grew too powerful or corrupt. When the Blade opposed the formation of the Covenant in the wake of the Sangheili-San 'Shyuum War, the order was hunted to near extinction by forces loyal to the new theocracy and its very memory was suppressed in the following centuries by religious edicts and decrees. Though the Blade survived the purge, it clung to existence as only a shadow of its former self and was able to truly reemerge only in the