Second battle of Christophsis At least two years after the Battle of Christophsis , a second battle took place on the planet Christophsis during the Clone Wars . After deducing that the Jedi Master Quinlan Vos had fallen to the dark side of the Force , the Jedi Council sent him on a mission to kill the Separatist leader Count Dooku in order to test his loyalty . From Vos ' lover Asajj Ventress , the Jedi learned that Dooku ' s dreadnought would be visiting Christophsis . Together , Vos and Ventress traveled to Dooku ' s flagship where Vos managed to engage in a lightsaber duel . Unknown to Vos , the Jedi Obi - Wan Kenobi and Anakin Skywalker tailed along . When Vos failed to kill Dooku and instead demanded that the Sith Lord lead him to his master Darth Sidious , the Jedi were presented with irrefutable evidence of Vos ' collusion with the Separatists . Kenobi and Skywalker arrested Vos and Dooku but the duo managed to escape following a confrontation aboard the " Venator " - class Star Destroyer " Vigilance " . Together with Ventress , Vos and Dooku attempted to flee aboard Dooku ' s dreadnought but were shot down . After crash - landing their starship , the " Banshee " , on Christophsis , the trio trudged to a local Separatist base there were Dooku contacted Darth Sidious to secure passage offworld . Kenobi and Skywalker subsequently launched an attack on the fortress . Ventress was killed during a duel between Vos and Dooku . Following a climatic confrontation , Vos managed to reject the dark side by refusing to kill Dooku . Vos was taken into Republic custody and subsequently pardoned . Meanwhile , Dooku escaped offworld with the help of Darth Sidious . Prelude . Following Count Dooku ' s massacre of civilians on Mahranee , the Jedi High Council sent Master Quinlan Vos on a mission to assassin ate the Separatist leader . For this mission , Vos partnered up with the Nightsister Asajj Ventress , who instructed him in the ways of the dark side of the Force . Ventress was Dooku ' s former Sith apprentice and wanted revenge against the Sith Lord for abandoning her . After a brief stint working together as bounty hunter s , the two Force - users attempted to assassinate Dooku on Raxus . However , Vos was captured and Ventress was forced to flee into hiding . In Dooku ' s captivity on Serenno , Vos was torture d and brutalized by the Sith Lord . After holding out , Vos embraced the dark side after learning that Ventress had murdered his former Master Tholme . Burning with hatred , Vos spurned Ventress ' attempts to rescue him during a dangerous mission to Serenno . For the next several months , Vos took his place as Dooku ' s new Sith apprentice and assumed the persona of " Admiral Enigma " . As " Admiral Enigma " , Vos inflicted several defeats on the Galactic Republic . After realizing that the Jedi would eventually discover his identity , Vos arranged to be rescued by the Jedi and Ventress . While his Jedi colleagues were convinced that Vos was still loyal to the light side , Ventress sensed that he had embraced the dark side . Back in the Jedi Order , Quinlan Vos used his position to play a double game with both the Republic and the Confederacy . He leaked intelligence about two military operations to Count Dooku . In secret , Vos wanted to curry favor with Dooku in order to force the Sith Lord to reveal his master , the elusive Darth Sidious . However , these two suspicious incidents led the Jedi Order to rightfully suspect that they had a traitor within their ranks . After Master Yoda deduced that Vos had indeed embraced the dark side , the Jedi Council sent him on a mission to assassinate Count Dooku . Viewing the mission as a second chance to destroy Dooku and Sidious at the same time , Vos accepted the mission and informed his lover Asajj . While Ventress was initially upset about Vos taking on another mission , she relented in return for being allowed to accompany Vos on his mission . Agreeing to help Vos complete the mission , Ventress revealed to the Jedi Council that Dooku would be visiting the planet Christophsis in his " Providence " - class dreadnought . Earlier , the Jedi Council had pardoned Ventress of her crimes in return for helping to rescue Vos . While some members of the Jedi Council still distrusted Ventress , Vos vouched for her and the two Force - users were able to proceed with their mission . The battle . A test of loyalty . Quinlan Vos and Asajj Ventress traveled to Christophsis on Ventress ' starship the " Banshee " . Upon reaching Dooku ' s dreadnought , Ventress opened the ship ' s doors so that Vos could leap into the dreadnought ' s hangar . Meanwhile , Anakin Skywalker and Obi - Wan Kenobi used a captured Separatist shuttle and two reprogrammed battle droid s to infiltrate Dooku ' s flagship with the intention of keeping an eye on Vos . While their reprogrammed battle droid s distracted the droids in the hangar bay , the two Jedi took the opportunity to head to the observation room , where Dooku was reported to be heading . As expected , Dooku headed there where he was greeted by Vos , who had been captured by several battle droids . While hiding behind a desk , Kenobi and Skywalker watched as Vos parried with Dooku in a lightsaber duel . Despite gaining the upper hand , Vos failed to deliver the final blow and instead grabbed the Sith Lord by his hair and slammed his head against the floor . Vos then demanded that Dooku reveal the identity of the elusive Darth Sidious . When Dooku refused to cooperate and instead suggested that Vos join forces with him to defeat Sidious , Vos refused to become his apprentice and instead Force choke d Dooku . In the end , Dooku agreed to lead Vos to Darth Sidious ; confirming the Jedi Council ' s fears that Vos was in collusion with Dooku . Having sufficient evidence to prosecute Vos , Kenobi and Skywalker sprang up from their hiding place and promptly disarmed Dooku and Vos . Despite Vos ' protestations , Kenobi responded that he had already been give more than one chance . After escaping aboard their stolen Separatist shuttle , the two Jedi returned to the " Venator " - class Star Destroyer " Vigilance " . On the way , they informed Clone Commander Cody and the Jedi Knight s Akar - Deshu ( " Desh " ) and Kav Bayons about Vos ' treason and Dooku ' s capture . The Jedi and clones made preparations to detain the two Force - users and to execute their prisoners if the Jedi Council gave such orders . Escape from the " Vigilance " . Upon landing in the " Vigilance " hangar bay , Quinlan Vos and Dooku were surrounded by twenty - four armed Clone trooper s , who had been handpicked by Commander Cody for this sensitive task . They were escorted by Desh and Bayons ; the former of whom was deeply hurt by Vos ' betrayal since they had previously been friends . While Kenobi and Skywalker went to confer with the Jedi Council about the recent developments , they assigned Desh , Bayons , and the clones to secure the prisoner s . As their clone and Jedi escorts were leading them to the ship ' s brig , Vos tricked Desh into approaching him . After verbally attacking the Jedi , Vos levitated Desh ' s lightsaber and used it to free Dooku from his bonds . The count emulated his ally and then grabbed Bayons ' s lightsaber . After Dooku killed a Clone trooper with his lightsaber and hurled Cody against the corridor and bulkhead , he freed Vos from his restraints and then struck Bayons and four more Clone troopers with Force lightning . Following a brief lightsaber duel , Vos managed to overpower his former friend Desh and Bayons by using Desh ' poison ous stinger to kill Bayons . To save his former friend the horror of dying an agonizing death , Vos killed him with his lightsaber . Meanwhile , Dooku managed to kill the remaining Clone troopers with the exception of Commander Cody , who sustained a broken leg during the skirmish . Having overpowered their captors , Vos contacted Ventress and told her to park the " Banshee " beside the " Vigilance " frontal hangar doors . Ventress reluctantly helped to evacuate Vos and Dooku . Following a tense reunion between Ventress and Dooku , the trio agreed to head to the Separatist dreadnought above Christophsis . However , the " Vigilance " under Skywalker ' s orders opened fire on the " Banshee " , damaging the ship and causing it to crash onto Christophsis below . The three travelers managed to survive their rough landing and trudged their way across the planet ' s crystal line surface to a Separatist base . Dooku sustained a broken arm and lost a considerable amount of blood as a result of the crash . Shortly later , Kenobi and Skywalker landed their Jedi shuttle at the crash site . After they and their Clone escorts Threepwood , Tracker , and Boil inspected the wreckage , they were able to deduce that the fugitives had survived and that one of them was wounded . Kenobi then secretly contacted Ventress via hologram and informed her that Vos had turned to the dark side and partnered with Count Dooku . He told her to convince Vos to surrender or they would be forced to execute him . Ventress informed Vos who told her that they were close to the end of completing his secret mission to destroy the Sith . Meanwhile , Kenobi and Skywalker received orders from Windu to execute all the fugitives . Assaulting the Separatist base . Vos , Ventress , and Dooku eventually arrived at the Separatist base , a large crystal that had been hollowed up into a tower and base . Upon arriving , they were greeted by hundreds of battle droids who led the three fugitives into the base . Upon reaching the command center , Dooku was informed that Darth Sidious had been trying to contact him . Dooku ordered them to leave the room while he conferred with his Sith master but Vos and Ventress insisted on staying . The duo witnessed a hologram of the enigmatic Sith Lord , who wore dark robes to hide his identity . When Darth Sidious inquired about Vos , Dooku claimed that he was his assassin . With Dooku ' s presence on Christophsis exposed to the Republic , the Sith apprentice pleaded for his master to send a ship . Sidious replied " perhaps " before disappearing . Before Vos could argue with Dooku about calling him an " assassin " , Republic forces under Kenobi and Skywalker began bombarding the crystal tower ; forcing Vos , Ventress , and Dooku to flee to safety . The two Jedi General s had deployed their shuttle and several ARC - 170 starfighters to bombard the Separatist base . Skywalker was about to order that walker s be deployed when Kenobi managed to convince him to order a halt to the bombardment so that they could enter the Separatist base and find the fugitives . Ventress , Vos , and Dooku survived the bombardment but were wounded by falling debris from the crystal structure . Ventress herself sustained a broken arm . Together , the three Force - users made their way to a large crystal boulder , a camouflaged outlying building . This crystal structure was an inner sanctum within the crystal Separatist base . Despite their injuries , Vos followed Dooku in the hope of reaching Sidious ' ship and killing the two Sith Lords once and for all . Meanwhile , Separatist battle droids engaged the advancing Clone troops and Jedi . While making his way inside the structure , Dooku was knocked unconscious by a blast which also opened his old crash injury . While Ventress wanted to let Dooku die , Vos insisted on saving him and went outside to help the battle droids fight off the advancing Republic forces . When Dooku stirred , he taunted Ventress by claiming that Vos had more potential to be a Sith Lord than her , whom he derided as a " grunt . " Ventress responded that Vos had " bigger plans " for Dooku which neither she nor Dooku were aware of . Meanwhile , on the Republic lines , Kenobi and Skywalker identified the Separatist inner crystal sanctum . Kenobi convinced Skywalker to order a ceasefire to the assault so that the two Jedi could sneak into the fortress through the back in order to trap the fugitives . Back in the Separatist crystal sanctum , Ventress confronted Vos about his decision to join Dooku and the dark side . Vos responded that he did it for the two of them and insisted that he knew what he was doing . Having experienced the dark side , Ventress warned her lover that it was a fraught and unhappy path . At that moment , she was filled with the power of the Living Force . Before Vos could respond , Dooku suddenly attacked him with a wave of Force lightning that Ventress blocked with her body . Though Vos managed to stop Dooku , Ventress was fatally wounded . Dooku then attempted to goad Vos into killing him . But realizing that this led to the dark side , Vos refused and reaffirmed his Jedi identity . While Dooku fled , Vos comforted his dying lover . Aftermath . Obi - Wan Kenobi and Anakin Skywalker came across a distraught Quinlan Vos cradling the body of Asajj Ventress . Together , the three Jedi fought their way out of the Separatist base but were eluded by Count Dooku , who escaped with the help of reinforcements sent by Sidious . Due to his earlier actions , Vos was detained in the " Vigilance " brig during the journey back to Coruscant . Out of respect for Ventress ' s actions in helping the Jedi , her body was kept in stasis aboard the ship . Back at the Jedi Council , Vos confessed that he had fallen to the dark side and joined Dooku in an attempt to destroy the two Sith Lords . He took responsibility for his actions under Dooku ' s campaign , for sabotaging the Republic operations at the asteroid base and the Vanqor listening post , and for killing Bayons , Desh , and the Clone troopers aboard the " Vigilance " . Vos also told the Jedi Council of how Asajj had brought him back to the light side . During the hearing , Kenobi spoke in favor of both Vos and Ventress . Firstly , Kenobi argued that the Council ' s decision to use Vos to assassinate Dooku had driven him to the dark side . He highlighted Asajj ' s actions to help the Jedi against the Separatist and backed - up Vos ' account that she had brought him back to the light . As a result , the Council decided to pardon Vos for his crimes and to give him another chance to serve the Order . Following the proceedings , Vos and Kenobi visited Dathomir where they laid Ventress ' body to rest .