However, Opress soon realized he was being used by Ventress and betrayed both her and Dooku, eventually returning to Dathomir and being sent on a quest by Mother Talzin to seek his long-lost brother and Talzin's son Maul. After murdering his beloved brother Feral in a display of loyalty to Ventress, Opress entered the Clone Wars as a Dark Acolyte, serving as an enforcer in Dooku's Confederacy of Independent Systems.

In accordance with their plot against Dooku, Mother Talzin and her Nightsister witches employed their dark magic to grant Opress fearsome abilities, such as a strong, raw connection to the Force and domineering physical power, while also placing him under their control.

Originally a tribal leader on Dathomir, Opress was handpicked by the Nightsister Asajj Ventress to become her 'mate' and servant following her grueling tests of Selection, as part of her bid for revenge on her former Master, the Sith Lord Count Dooku. Savage Opress ( pronounced / sə'vɑʒ oʊ'pres/) was a Force-sensitive Dathomirian Nightbrother who became a Sith apprentice under Count Dooku and later became a Sith Lord, apprenticed to his brother, the renegade Sith Lord Maul, during the Clone Wars.