Around 3 ABY, the Scourge's forces launched an assault against Fortress Vader, located on the planet of Mustafar, with the goal of possessing the Sith Lord Darth Vader to exploit his understanding of the Force. This endeavor proved unsuccessful, as Vader successfully resisted the infection. The Scourge later attempted to infect Vader once more during an attack on Vader's flagship, the Executor, and subsequently a third time with another attack on Mustafar.