The Scourge crisis, also referred to as the droid plague or the "scourge of the droids," denotes a virulent infection that affected droids and cyborgs. It propagated throughout the civilized galaxy during the Galactic Civil War, following the defeat of the Crimson Dawn syndicate. In the climactic battle of Crimson Dawn's war against the Sith, Lady Qi'ra unlocked the Fermata Cage in an attempt to imprison the Sith Lords Darth Sidious and Darth Vader, the leaders of the Galactic Empire. Upon opening the Cage, a small disc fell out, unbeknownst to the two Sith, this piece of technology had been locked away by ancient Sith. Following the Knights of Ren's disruption of the Cage, which freed the two Sith but unleashed the Force Wave, Qi'ra's forces were decimated by the Imperial fleet. In the wake of Crimson Dawn's demise, one of Qi'ra's allies, the anti-Sith artificial intelligence known as the Spark Eternal, escaped into the disc and merged with the ancient Sith technology, giving rise to the "Scourge."
The newly formed entity developed an insatiable hunger and spread as a droid infection to access their memory banks. This Scourge infection wreaked havoc on both the Empire and the Alliance to Restore the Republic. Fuelled by its growing corruption of droids, the Scourge determined that ceasing its spread would lead to its destruction, prompting a campaign to dominate the galaxy, with the ultimate goal of controlling the Force. The Scourge corrupted droids and cyborgs, seeking a method to conquer fully organic beings, thereby assimilating every being in the galaxy. This assimilation would eliminate all enemies. Consequently, the Scourge could concentrate solely on the memories and information it had accumulated during its expansion. Vader, as a cyborg, was the Scourge's primary target due to his susceptibility to corruption. The warrior-priest droid Ajax Sigma played a crucial role in halting the Scourge.
After his failed attempt to punish his Sith Master Darth Sidious during the prevented [Scourge of Coruscant](/article/scourge_of_coruscant], Vader willingly merged with the Scourge, aiming to surpass his master in power. It remained uncertain whether the Scourge controlled Vader or if Vader had seized control of the Scourge for his own purposes. In reality, Vader swiftly detached his armor from the larger Scourge entity and endeavored to create his own version of the infection under his command. During the Battle on Epikonia, the Scourge finally learned to transfer itself into organic beings and seized control of Luke Skywalker's body, declaring its intention to become the new Force. However, at that precise moment, Sigma destroyed the Scourge's primary body, liberating all organics, including cyborgs, and droids from its grasp.