Karras

Karras is the main antagonist in Thief II: The Metal Age and the head of the Mechanist Order. He was a brilliant inventor, sociopath, genius, and prophet who split from the Hammerite organization to found his own faction, due to extremist beliefs, namely that all organic life was inherently flawed. He also had a distaste towards the conservative, insular nature of the Hammerites and their slow technological progress. Though Karras suffered from a speech impediment, he was very charismatic and commanded a loyal army of Mechanist followers.