In 2009, Horath was variously described as a computer or as a cybernetic creature. Whatever his nature, he had the power to destroy or create worlds at will. According to Mr Smith, Horath used his power to crush the civilisations of all but the most primitive of planets.
Horath was overthrown circa 1000 BC. He could not be killed, so his consciousness and his body were believed to have been separated, with one part going into a crystal in the Kaldeann Cluster, and the other part being left in an unknown place (speculated to have possibly been another dimension); a place which could be accessed by placing the piece of Horath's consciousness within the Kaldeann crystal into a Tunguska scroll, which would hone in on its location. The scroll and crystal could be placed inside the heart of a stone monument similar to Stonehenge. This would allow entry to this place on the then-primitive planet Earth.
In 2009, Mrs Wormwood and Commander Kaagh sought to revive Horath and use him to attain power over the whole galaxy. A portal leading to Horath appeared, which Kaagh closed. Sarah Jane then used her sonic lipstick to destroy the crystal and scroll, ensuring no one would find Horath again. (TV: Enemy of the Bane)