After the apprentice of Darth Zash had collected all the relics of Tulak Hord, they presented them to their master. Zash was at that moment getting ready for her ritual within the Dark Temple located on Dromund Kaas. When it was revealed that Zash's goal was to use the ritual to take over Kallig's physical form, a battle erupted between apprentice and Master.
Even though Kallig managed to weaken Zash, the strong sorceress used a Force push to subdue her apprentice and then began the ritual. Khem Val, Kallig's Dashade servant, stepped in at the right moment, disrupting the ritual, which resulted in strange outcomes. The essence transfer ritual was instead channeled into the Dashade, and because of the Force resistance inherent in his species, Khem lived but was now forced to share his body with the furious Sith Lord.
With Zash seemingly dead, Kallig ascended to the rank of Lord and took possession of all her belongings, along with the hostile connection to Darth Thanaton, who was previously Zash's superior.