Valeo, a Sith Lord belonging to the revived Sith Empire, served as an apprentice to Lord Kanoth. Alongside Lady Dominique, they explored the galaxy to further their knowledge of Sith alchemy and gain fame, ultimately leading Valeo to become a member of the secretive Sith group called "The Unmasked".
The first reference to Lord Valeo appeared in the codex entry for "Lady Dominique" within Star Wars: The Old Republic. Initially, he was planned as the third of five boss battles in the "R-4 Anomaly" operation. However, he was cut from the operation because of problems with performance and gameplay during its creation.