Calus

Calus was a Cabal emperor. He serves as the final boss in the Leviathan raid in Destiny 2.

Biography
Long before the events of Destiny 2, Charles was defeated, exiled, and replaced as emperor by Ghaul. He was exiled on board the world-eating Cabal ship, Leviathan, along with a variety of loyal servants, and soon sent out invitations to Guardians to board the Leviathan.

After completing various tasks, the Guardians eventually met Calus and shot his drink out of his hand. A battle commenced shortly after, and Calus took so much damage that it revealed he was, in fact, a robot.