Melusar was born on Dromund Kaas, a planet controlled by the Prophets of the Dark Side and was once the capital of the resurgent Sith Empire. As a result, he developed a strong hatred towards any and all Force-sensitives. He also despised the fact that the Empire had Force-users of its own. Melusar had a profound hatred of the Republic, as he believed that they left the citizens of Dromund Kaas to rot and erased all records of the planet.
Shortly after taking command of the Commando Division of the 501st Legion, Melusar approached commandos Niner and Darman, telling them of his hatred of Force-users, including Imperial ones, and asked the two commandos to report directly to him. He secretly asked them to help him in his quest to rid the galaxy and Empire of Force-users. Darman, whose wife Etain had died during the Great Jedi Purge, agreed to Melusar's proposal. When Darman asked Roly to get a ship and and supplies so he and Niner could go to Mandalore, Melusar agreed because Darman said it was to find some old intelligence contacts. Niner questioned this decision, but Darman stated that he believed all Force-users to be evil.