The Invasion of Ziost was a military operation in 3637 BBY during the Galactic War between the Sith Empire and the Galactic Republic that saw the former Sith Emperor Vitiate take control of the entire planet of Ziost and, despite attempts by the Republic and Empire to break his hold, bring about a horrific cataclysm—feeding off of the planet's population, Vitiate used a ritual of Sith magic to consume all life on the world, just as he had done to his own homeworld of Nathema more than a millennium earlier.