[member="Fatty"] No Directive 12 (GA invasion of Coruscant), Mindabaal or Sekalus (the Croa virus arc)?
If anyone is willing to add more details about these disasters, feel free to do so.
Coruscant: Directive 12 resulted in wanton devastation perpetrated by the One Sith in the defense of its capital in the face of advancing Galactic Alliance forces, causing the deaths of dozens of millions of civilians (primarily in the Financial District, Valley of the Lords) in an attempt to cover the retreat of the One Sith armies. Darth Centax is rumored to be involved in the widespread destruction.
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Mindabaal: Perpetrated at the height of the civil war between the One Sith and what ultimately became the Sith Order, the battle between these two Sith groups resulted in planet-wide devastation that left most cities of Mindabaal in ruins and both parties being equally complicit in destruction, amounting to a genocide.
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Sekalus: The Covenant of the Black Rose unleashed bacteriological weapons upon the population of Sekalus, turning them into Sithspawn against their will, later claiming to develop a cure that turned out to be the now-extinct Croa virus. Anyone who opposed the new rulers was ripped apart or turned into the undead, mind-controlled Sithspawn. Also, the people who were not infected were turned into breeders, with their children being taken away and turned into Croa.
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