Tenebrae's curse

Tenebrae's curse was unleashed concurrently with the Battle of Zakuul. When the Commander of the Eternal Alliance cast the spirit of the Immortal Emperor Valkorion out of his mind, the former Emperor's Wrath Scourge and the Jedi Knight Kira Carsen found and destroyed his original Sith body. This triggered a trap laid by Tenebrae: the destruction of this body was tied to a Sith ritual that released the plague into the air, thanks to the said ritual carved into his body centuries prior. Since Scourge and Carsen had already been affected similarly by the emperor in the past, they were not infected, but left comatose for more than a year.

Jedi Master Satele Shan led a mission to rescue Scourge and Carsen around 3628 BBY. The plague still lingered, however, and Shan and her followers were unknowingly infected. Within days, they were left in a nightmarish sleep, in which they slowly began merging into a hive mind. Scourge and Carsen, having been successfully rescued by the Jedi, captured them and kept them quarantined in a transport vessel flying an undetermined course through unsettled sectors of the Outer Rim Territories.

Kira later realized that the ritual carved into Tenebrae's original body was not a plague, but an imprint, an echo of his original self meant to manifest when both his body and spirit were destroyed. Although the imprinted spirit did not maintain memories of the original, it still possessed the same powers.

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