Dark illusion The Force power of dark illusion gave its user the ability to manipulate Force vision s to directly attack a selected target . Dark illusion was summoned through an ancient Sith ritual using both the connection of a Force - bond , one coming from someone with a link to the target , and reciting a Sith incantation in the old Balc language . Compounded with the blood of the bonded and Force lightning , as well as the dark side of the Force , dark illusion could reach its intended victim from across the galaxy . A different , but possibly related light - side ability was projection . During the galactic conflict known as the Clone Wars , the Dark Lord of the Sith Darth Sidious used dark illusion to attack Grand Master Yoda of the Jedi Order , exploiting his Sith apprentice Darth Tyranus ' bond to Yoda for the ritual . Also using the power of the long - deceased Sith Lord Darth Bane ' s tomb , Sidious was able to , while on Coruscant , reach Yoda on Moraband , the ancient homeworld of the Sith . Description . The Force power known as dark illusion was one of the dark side of the Force . The power allowed the wielder to manipulate Force vision s to affect a selected target . To harness dark illusion , an ancient Sith ritual was required . This involved the blood of someone who was Force - sensitive and had a Force - bond with the intended victim . The bonded one then needed to focus on their bond with the target , and once the blood was drawn , it had to be compounded with an array of Force lightning in a sacrificial altar basin . An old Sith incantation was spoken in the Balc language to complete the ritual , at which point dipping one ' s face in the powered basin would allow one to access dark illusion . The resulting Force visions could be used to impersonate specific individuals , resembling them in both physical appearance and voice . The illusion could also be amplified using a source teeming with dark side energy , and could make the affected target believe that they were elsewhere during these visions . Applications . The art of dark illusion was ancient , known only to a few Sith . When the Dark Lord of the Sith , Darth Sidious , sensed that Jedi Master Yoda was on Moraband , the ancient Sith homeworld , he sought answers to why the Jedi had ventured there and also hoped to break the Grand Master ' s will . For this reason , he conjured the power of dark illusion , using his own sacrificial altar basin from a lair on Coruscant . As Yoda traveled into the tomb of Darth Bane , an archaic Sith Lord from a thousand years prior , Sidious further amplified the dark illusion ' s power with the power of the tomb , which had been used as a Jedi sacrificial chamber in centuries past . This power allowed Sidious to tempt Yoda using familiar scenarios in the visions that followed . Ultimately , Sidious sought to subjugate the galaxy , but once Yoda refused the Sith Lord ' s temptations and visions , he knew he needed more time before the Jedi could be defeated and the Sith could return to power . Users . During the Clone Wars , a conflict that tore apart the galaxy and divided the Galactic Republic , the Sith Lord Darth Sidious and his Sith apprentice , Darth Tyranus , used the ritual to summon the power of dark illusion . Sidious closely guarded his Sith identity , acting as the Supreme Chancellor of the Republic Palpatine , as did Tyranus , who was publicly known as Count Dooku , the leader of the Separatist Alliance . When they both felt the presence of Master Yoda , Dooku ' s former teacher , on the planet Moraband , Dooku was called to Coruscant to confer with his Sith Master . In an abandoned industrial sector of Coruscant known as the Works , Sidious informed his apprentice that they would be exploiting Dooku ' s Force - bond with Yoda , which the two had established during their time together in the Jedi Order , to find out why Yoda had ventured to Moraband and to break his will ; prior to Yoda ' s arrival on Moraband , only the Jedi Council member Ki - Adi - Mundi suspected that the Sith were capable of exploiting Yoda ' s bond to Dooku . Over a sacrificial altar basin , Sidious cut Dooku with a knife to draw his blood , dripping it into the water - filled basin , and recited the Sith incantation in Balc . Together the Sith Lords then jolted the basin with Force lightning , and once Dooku focused on his bond with Yoda , Sidious harnessed the power of dark illusion . When Dooku expressed concern over Yoda sensing their presence , Sidious said he would come to Yoda with someone familiar as he dipped his face into the sacrificial altar . Sidious pretended to be the long - dead Jedi Master Sifo - Dyas , imprisoned in the tomb and sacrificial chamber of the ancient Sith Lord Darth Bane through his vision to Yoda . Sidious tempted the old Jedi Master with an opportunity to — at last — learn Darth Sidious ' s true identity , since the Jedi were aware only of his existence . When Yoda refused , Sidious entranced Yoda further by using the power of the tomb to enhance his illusion and make the Jedi Master believe himself to be back on Coruscant . Yoda found himself in the presence of Jedi Knight Anakin Skywalker and a squad of clone trooper s from the Grand Army of the Republic ' s 501st Legion , in an ongoing pursuit of both Dooku and Sidious in the Works . When the Jedi cornered the two Sith Lords in the illusion , the 501st troopers were quickly incapacitated and , in turn , Skywalker beheaded Dooku as Yoda pursued the hooded Sidious . The two briefly dueled before the vision of Sidious threatened to kill Skywalker while simultaneously attacking Yoda . The Jedi Master was then presented with a choice : Either learn the identity of the Sith Lord once and for all or save Skywalker , whom Sidious had thrown off a catwalk . Yoda chose the latter and sacrificed himself , falling into the depths of Coruscant with the vision of Sidious as the dark illusion fell apart . After the illusion ceased , Sidious arose from the altar basin and informed Dooku that they had failed to break Yoda ' s will , and that they would need more time to defeat the Jedi . Unbeknownst to either of the Sith , Yoda had been put on trial by the ethereal Force Priestesses to learn the secret to immortality , and had passed when he defeated the dark - siders he encountered , including Sidious ' s own dark illusion . In addition , despite Dooku ' s presence throughout the ritual , only Sidious was in control of the visions presented to Yoda , leaving Dooku unaware of the foreshadowing of his own death or of Skywalker ' s eventual fall to the dark side . Near the end of the Clone Wars , Skywalker killed Dooku in the same manner he had slain the count in Sidious ' s dark illusion . Dooku ' s death became one of Skywalker ' s first steps into becoming Darth Vader , Sidious ' s new Sith apprentice , prior to the beginning of the Jedi Purge , which fulfilled Sidious ' s plot for the revenge of the Sith . Behind the scenes . The dark illusion Force power debuted in " Sacrifice , " the thirteenth episode of , which was released as the sixth and final season of the . Dark illusion was first identified by name in the " Sacrifice " episode gallery on StarWars . com . In the episode ' s script , the Sith incantation spoken by Sidious was noted as " Balc speech " and was written out as " " Kintik hadzuska sutta chwituskak ! Kintik hadzuska sutta chwituskak ! Jiaasjen Jidai , jiassjen Jidai ! " " . Darth Sidious , who recited the Sith incantation in Balc to summon the power of dark illusion , was voiced by Tim Curry .