Quintesson
The Quintessons are an ancient alien race. They are mostly mechanical beings, their main feature being a spherical body lined with five faces and tentacles along the bottom. Each face seems to have a separate personality.
Animated series
The Quintessons first appeared in 2005 during the events of Transformers: The Movie, where they are shown to capture prisoners for trial and feeding to their army of Sharkticons.
It was later learned that the Quintessons were the ones who created Cybertron as a factory world, and the Transformers as consumer goods. The Transformers eventually rebelled, and the Quintessons would abandon Cybertron.
During the events of The Return of Optimus Prime, a single Quintesson was captured by Sky Lynx to repair the body of Optimus Prime.