Battle of Thule The Battle of Thule was the final battle during the Dark Reaper crisis during the Clone Wars , in which the Republic managed to locate and destroy the Separatist superweapon . Moon assault prelude . As the Republic fleet neared Thule , Padawan Anakin Skywalker diverted a single " Acclamator " - class assault ship down to the surface of the planet ' s barren moon Sivvi to deal with the Separatists ' shield complex , landing in a large crater . Unfortunately , they were quickly detected by the CIS forces and two C - 9979 landing craft touched down around the crater ' s edge and deployed GAT fighter tanks , Armored Assault Tanks ( AATs ) , and armored mortar tanks to destroy the assault ship before it could offload all of its troops and artillery . Skywalker took control of a TX - 130S fighter tank and fought off the Separatist attack , allowing the Republic AT - XT walkers and Republic Troop Transport s to disembark . Taking to the cockpit of an AT - XT himself , Skywalker led a squadron of the bipedal walkers in escorting the convoy of Troop Transports carrying clone engineer s to the shield complex north of the crater . He and his men combated further attacks from GATs and AATs , but lost one of the three Troop Transports in the convoy to mortars . When they approached the complex , further resistance was mounted in the form of Separatist gun towers and OG - 9 homing spider droids in addition to continuing assault from several AATs . When they were finally destroyed , Skywalker proceeded to take down three auxiliary reactors outside the complex as the clone engineers managed to slice their way into the control systems outside , bringing down the thick , armored doors . Their task completed , the engineers and the Troop Transports peeled off from the entrance as Skywalker piloted his AT - XT walker through the heavily defended generator complex and destroyed the four charger couplings that supplied power to the shield , disabling it and allowing the bulk of the Grand Army ' s forces to land on Thule . The battle . Air strike . After the Battle of Sivvi , Jedi Master Obi - Wan Kenobi and a clone crew flew a LAAT / i gunship into battle on Thule , to clear a Separatist landing zone of all anti - aircraft emplacements and droid presence , including several OG - 9 homing spider droids . When the grounds had been cleared , Mace Windu landed a pair of " Acclamator " assault ships and began offloading gunships and armored walkers , and disembarking troops . Among the new trooper arrival was a division of clone engineers that Windu tasked with disabling the internal shields of the energy farm s surrounding and supplying power to the Separatists ' command center . Each was well guarded by droid tanks , requiring Kenobi to clear the perimeter of each before deploying the engineers aboard his gunship and then safeguarding them as they worked . When the farms ' shields were down , they became easy targets for the LAAT / i gunship ' s weapons and were soon destroyed ; Kenobi then turned his attention toward the Separatist main command center . With the loss of power resulting from the energy farms being brought down , there was little the command center could do to withhold the attack and quickly fell , crippling Separatist communications and their ability to mobilize forces across the planet . Ground attack . After the fall of the communication command center , Windu teamed with fellow Jedi Master Luminara Unduli , leading a squad of AT - XT walkers to attack two droid starfighter hangars that were allowing the Separatist the advantage in the air . Once they were destroyed and the Separatists ' air presence neutralized , the two Jedi Generals left their walkers in favor of piloting " Saber " - class fighter tanks and turned their attention toward the droid foundries that still churned out AATs and mortar tanks . Unable to penetrate the thick armor with the weapons aboard their tanks , the two Jedi instead took up defensive roles for the more heavily armed and slower - moving AT - TE walkers , protecting them from the incoming fire of more nimble craft while they moved to destroy the foundries . When the walkers had obliterated the foundries and cut off the Separatists ' supply of reinforcements , Unduli and Windu pushed forward toward the gates of the ancient Sith city and capital of Thule : Kessiak . On the way , however , the two encountered a pair of Protodeka s that they had to fight their way past before finally arriving at Kessiak ' s outer wall . There , Unduli informed Windu that Master Yoda had sent in an additional " Acclamator " assault ship to land reinforcements . But just as Windu approached the gates , Count Dooku ' s hired mercenary , Cydon Prax , attacked him in his personal Dreadnought battle tank , destroying Windu ' s own fighter tank . Though he managed to escape the blast and survive , Windu was forced to fight on foot as he made his way across the battlefield and into an underground tunnel complex that led to the gate controls . After cutting down countless battle droids and destroying numerous dwarf spider droids , Windu reached the controls and opened the city gates to the Republic forces en masse . As Windu ' s forces began entering Kessiak , Skywalker ' s own strike force arrived from Sivvi and launched an attack from the opposite side of the city . While legions of clones battled overwhelming numbers of battle droids and AT - TE walkers clashed with homing spider droids , Skywalker raced toward the city center in a fighter tank , blasting through roadblocks and Separatist forces alike . Eventually , he came across Count Dooku and Cydon Prax , guarding the Dark Reaper in his Dreadnought tank . Dooku took his leave — claiming " more important tasks " requiring his attention — though not before ordering Prax to kill Skywalker . The two dueled in their respective vehicles and Skywalker emerged victorious , destroying Prax and moving on to engage the Dark Reaper without awaiting backup , with the spirit of Ulic Qel - Droma as his guide . Piece by piece , the Jedi first crippled the Reaper and then finally destroyed the Force Harvester — the source of the Reaper ' s power . With the Harvester destroyed , the Reaper could no longer function and quickly fell from the air , powerless and defeated . Aftermath . The Reaper was , for a second time , destroyed . However , the knowledge Anakin gained from Ulic Qel - Droma , including immunity to the Reaper ' s effects , was yet another thing that set him apart from his master and caused him to act more arrogantly towards Kenobi . It was possible that the battle and the power Skywalker had gained throughout the Dark Reaper Crisis indirectly led him to take another step towards the path of the dark side of the Force . Count Dooku had escaped , eluding capture yet again , and the Republic forces prepared to depart for the Mirgoshir system . Mace Windu regarded the battle as a turning point in the war , but Yoda was less convinced , pointing out that the war was still far from over .