Ravage

Ravage was a warrior of Amital. He seized the throne by force, but the Republic fought against him and eventually defeated him, though at great cost. He was taken to Earth and bound in a psychomolecular prison which resembled a standing stone. The twelve sentries who had brought him there also turned themselves into stone to watch over him. The thirteen stones became known as the Stone Whisperers, and their origins passed into myth and legend.

Thousands of years later, in 2008, Ravage's mind was freed when his stone absorbed energy from Professor Jacqueline Lauton's scans, and he took possession of Luke Smith. Ravage believed that Luke's young and impressionable mind would make it easier for him to completely take over and destroy Luke's personality. While Luke fought a mental battle against Ravage, the twelve other stones turned back into sentries and pursued him. After a great deal of effort, Luke, supported by his mother, Sarah Jane Smith, and his friends, Maria Jackson and Clyde Langer, eventually succeeded in expelling Ravage from his mind, dispersing his essence. (SJAA: The Thirteenth Stone)