Darth Mortem

Darth Mortem was the founder of the new sith eternal empire and was the master of Darth Bellum. His origins are mostly unknown except that he was from the planet exegol. He disappeared towards the beginning of the war somewhere in the unknown regions. Darth Mortem was regarded as the strongest sith to live (so far). He was killed at the sith capital when Darth Corruptorem (With the help of Darth Bellum) stabbed him and later buried Mortem on his home planet Exegol. His death marked the end of the first generation of the sith eternal and the beginning of the second. Later his long lost apprentice Darth Diablo returned awakened by the disturbance in his masters death