The Imperious Leader is the supreme ruler of the Cylons in the original Battlestar Galactica TV series and associated media. As the highest authority within the Cylon Empire, the Imperious Leader is the one who determines all of the Cylons' campaigns across the galaxy and has decreed the extermination of humanity.
The Imperious Leader resembles the reptilian species that created the Cylons to begin with, though it is entirely mechanical and has no organic components. Built with three distinct brains, the Imperious Leader possesses unparalleled computational power, making it an excellent strategist and commander. In the event that the Imperious Leader is destroyed, another is selected from an IL-series Cylon.
While various artworks depict the frontal appearance of the Imperious Leader, its face was never revealed on-screen during the TV series and it was only ever seen from the back or overhead, or otherwise obscured by shadow.