Monster " Monster " is the thirteenth episode of the ' . It aired on January 14 , 2011 . Official summary . " " When Count Dooku calls upon the Nightsisters seeking a replacement for Ventress , she and her kin seize the opportunity to exact revenge . Ventress visits the far side of Dathomir and the males of the planet seeking the most brutal and powerful warrior among them . Talzin has Asajj secretly select a warrior from the distant Nightbrother village : Savage Opress . With the power of dark magic , Talzin transforms Savage into a hulking warrior ultimately loyal to Asajj . She then delivers Opress to Dooku , where he will serve as his secret Sith apprentice in a plot to overthrow Darth Sidious . " " Plot summary . Count Dooku travels to Dathomir to meet with Mother Talzin so that she may aid him in procuring another personal assassin to replace Asajj Ventress . He also attempts to form an alliance with the Nightsisters , an offer that Talzin rejects for unspecified reasons . Talzin asks if he recalls the Sith warrior Darth Maul , to which Dooku responds that he does , but remembers that he was killed by Obi - Wan Kenobi a decade ago on Naboo . Talzin suggests recruiting a male from a village from the other side of the planet , a warrior of Darth Maul ' s caliber , though she cautions him that male Zabrak s are often harder to control . Believing the Jedi to have perpetrated a previous attack on him and Ventress to be dead , Dooku agrees to this offer . After Dooku has departed , Talzin sends Ventress herself to the village to select one of its warriors to serve their revenge plans against the Count . Following a preliminary weeding out of the less capable potential candidates , Ventress sets up three tests to aid in the selection : A test of arms , in which the candidates attack Ventress ; a test of darkness , in which they have to face Ventress hidden in the shadows and their own fear ; and a test of skill , in which they have to elude Ventress while navigating a maze of rising stone blocks . By the beginning of the third contest , only two contenders remain alive : Savage Opress and his younger brother Feral . When Ventress corners Feral and prepares to kill him , Savage steps in and faces her in single combat in exchange for his brother ' s life . Though he is defeated , Ventress is sufficiently impressed to accept him in her service . Back in their abbey , the Nightsisters use their mystical powers to increase Savage ' s strength and ferocity , turning him into a hulking brute , and putting him under Ventress ' complete control . As a final test of his loyalty to her , Ventress assigns Savage to kill Feral , who has been brought there as a prisoner , which he does with little hesitation . Deemed ready for his task , he is armed with blastproof armor and a mystically empowered vibro - ax and introduced to Dooku . Impressed , yet cautious , Dooku sends Savage to the jungle world of Devaron to take out a small Jedi temple located there . Savage arrives at the temple and quickly ends the ongoing fight between the temple ' s guardians and the invading droid forces , taking out Jedi Master Halsey and his apprentice Knox , along with their clone troops in a matter of moments . Thoroughly satisfied , Dooku takes Opress in as his new apprentice and promises to teach him in the ways of the Dark Side in order to eventually overthrow Darth Sidious and rule the galaxy . . .