Sith Emperor's ritual

During the time of the Great Hyperspace War, the Sith Lord Vitiate developed a ritual of Sith magic that granted him immortality and immense strength in the Force by ensaring the souls of the dead. Using the strength of eight thousand Sith Lords to power the Sith magic, Vitiate was able to strip the Force itself from the planet Nathema at the expense of every living thing on the world, and as the Sith Emperor of the reconstituted Sith Empire, he later developed an artificial version of the ritual by combining it with Sith alchemy and cybernetics. With the Sith magic, the Emperor was able to grant immortality to his favored servants, and he intended to use the ritual on a galactic scale in order to consume all life in the galaxy and thereby ensure that he would never be defeated. However, the Jedi Knight known as the Hero of Tython prevented the Emperor's agents from bringing about the sacrifice of thousands of lives that was necessary to start the ritual—but only for a time. With his plans exposed to the Empire, a now dethroned Vitiate turned on the Imperial world Ziost and used the strength of the entire world's population to carry out the ritual once more and consume all life on Ziost.

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