"It is you who fears death, 'Valkorion'. I do not. I will not kneel." -Marr's final words and last stand.
Darth Marr was a human male who was famous for never revealing his true face—the Dark Lord was perpetually encased in his personalized suit of battle armor, and rumor had it that the sight of Marr's visage was the reason Moff Xerxian committed suicide. Throughout his tenure on the Dark Council, Darth Marr's body slowly transformed as a result of immersion in the dark side of the Force, and by the time war broke out again with the Republic the Sith Lord was aware that his body would not last much longer. Marr was driven by a fierce dedication to warfare, one that bordered on zealotry. He believed that conflict was the only way that life evolved and grew stronger, and Marr's personal view was that death was inevitable—only cowards tried to avoid that which was a necessity. Darth Marr's power in the dark side gradually stripped him of emotion over the decades, leaving the man with a fraction of his humanity but a strong desire to ensure that the Empire survived.
Marr and the Outlander revealed their purpose being there was to destroy Valkorion but the latter offered that they join him instead. Darth Marr bluntly refused Valkorion's offer and proceeded to attack and defeat several of the Emperor's guards. Before Darth Marr could continue further, he received a direct hit of concentrated lightning from Valkorion's hand, killing the Sith Lord.