Battle of Cato Neimoidia ( Order 66 ) A battle took place on Cato Neimoidia during the end of the Clone Wars , in 19 BBY . The battle . Despite the efforts of Jedi Master Obi - Wan Kenobi and Jedi Knight Anakin Skywalker , the CIS forces on Cato Neimoidia were not defeated . Jedi Master Plo Koon , along with his clone pilots , was tasked with the mission to patrol the skies of the Neimoidian purse - world in his Delta - 7 " Aethersprite " starfighter . The Kel Dor Jedi patrolled the skies of the Separatist stronghold , on the lookout for any enemy fighters . On the bridges of the planet , the Republic UT - ATs , AT - APs and clone troopers fought against the Separatist droid forces to find a way into the cities . Meanwhile , a fleet of " Venator " - class Star Destroyers arrived at the planet . One of the ships was boarded by battle droids . X2 , one of the clone troopers onboard the ship , along with a contingent of clone troopers , were deployed to clear the hangar bays of the Battle Droids , and then to man an orbital strike cannon to bombard the separatist defenses on the planet . Afterwards , X2 boarded an ARC - 170 starfighter and then participated on the ground assault on the planet . Upon clearing the ground of tank droids for landing , X2 was supplied with a sniper rifle by Jedi Master Ferroda so he could supply cover fire for the troopers led by X1 as they advanced on the Viceroy ' s palace , and also destroyed an ion cannon ' s controls to prevent it from being used against the clone forces . This action also caused Ferroda to sense his Force potential and promised to allow the Jedi High Council to see him regarding it after the war is over . X2 then infiltrated the palace and , under X1 ' s orders , shut down the droid control terminal , thus shutting down all CIS droids on the planet . Order 66 . Flying near one of these bridges , Koon was unaware what happened in the ARC - 170 starfighter behind him . The Clone Captain Jag was contacted by Supreme Chancellor Palpatine who ordered him to execute Order 66 . Without hesitating , Jag pulled back a little in his fighter from the Jedi General and he fired his laser cannons . The Jedi Master ' s starfighter was hit and it exploded in mid - air , killing him . What remained of the fighter crashed into a building on the bridge - city , the explosion killing troops at a clone staging area . Newly arrived from Coruscant , X1 , and his brother , X2 , were under the command of Master Ferroda . After Order 66 was issued , X1 convinced X2 to strike down Master Ferroda . Horrified by what he had done , X2 turned his back on the newly formed Galactic Empire and fled to Dantooine . Aftermath . The Republic - turned - Empire had won the planet after the battle droids of the Confederacy were deactivated . The Emperor himself made law that surviving Neimoidian outcasts on the planet would be taken prisoner . Behind the scenes . The battle is covered in the game " Star Wars Battlefront : Elite Squadron " . The events concerning X1 and X2 use the PSP version as the basis . In the DS version , the game claims that months passed between the Battle of Coruscant when in fact far less time had passed . The DS version has X2 also destroying three power supplies for a force field around the planet prior to joining the ground battle . Originally , " " named the event as the Second Battle of Cato Neimoidia . However , the episode " Sabotage " depicted another battle prior to the first two that had been previously depicted in " Labyrinth of Evil " and " Revenge of the Sith " , respectively . Until official word is provided to resolve the discrepancy regarding the " Second Battle of Cato Neimoidia , " this article assumes that the " Revenge of the Sith " battle ' s name is currently conjecture .