Spearheaded by Jedi Master Echuu Shen-Jon, the Hunt for the Decimator was a military operation launched against Confederacy of Independent Systems General Sev'rance Tann.
This campaign commenced nearly at the same time as the outbreak of the Clone Wars. Shen-Jon's motivation to confront Tann stemmed from the loss of his pupil, Stam Reath, who was killed by the Separatist general during the First Battle of Geonosis.
Subsequently, Tann orchestrated a series of events that led to the Galactic Republic's's secret superweapon, the Decimator, being seized from research installations located on Eredenn Prime. Additionally, she acquired the activation sequences for the devastating machine from Alaris Prime.
Tann utilized the weapon to conquer the planet Sarapin, resulting in the death of Jedi Knight Jor Drakas and causing widespread panic throughout the Republic. In response to this critical situation, Jedi Master Mace Windu dispatched Echuu Shen-Jon, his new Padawan Naat Reath, and a contingent of clone troopers with orders to retake Mount Corvast, Sarapin's primary energy collection center. Shen-Jon's success in this engagement demonstrated his exceptional tactical abilities, rivaling those of Tann.
After the battle on Sarapin, Shen-Jon led his forces in relentless pursuit of Sev'rance Tann, eventually locating her on Krant. On one of Krant's moons, he captured a Trade Federation installation, intending to use it as a base for an invasion of Krant. However, Naat Reath was captured by Tann, causing Shen-Jon to succumb further to the dark emotions that had been growing within him since his brother's death.
Shen-Jon followed Tann to Krant, battling through numerous Separatist strongholds, securing the Decimator facilities, and ultimately confronting Tann in her fortress. The Separatist general gave Shen-Jon an ultimatum: face her in single combat, or Reath would be executed. Shen-Jon accepted the challenge, defeated Tann, and brought the campaign to an end. Shen-Jon instructed Reath to return to the Jedi High Council, while he chose to go into self-imposed exile.