Shortly after the planet was colonised, Vorass went into the wilderness. He went mad from a combination of radiation and certain chemicals. He believed that Tarron spoke to him. He started the Vorassan cult and began killing and converting the colonists. At this time, the Kephra came to the planet and saw the problems they were facing. They stopped the Vorassan cult and made the inhabitants immune to the radiation.
Centuries later, the Kephra saw the Tarronians could develop the technology necessary for a Holoprobe. With this technology, they would see that the holovid was a fake. To prevent this, they kidnapped Vorass from the past with a Time Scoop to kill the top scientists in the field. They also developed Holoprobes of their own and denied all requests to reconstruct the old holovids. The First Doctor and Dodo investigated and found the faked holovids. The Kephra were banished from Tarron and the Tarronian civilisation suffered from anarchy. (PROSE: Tarnished Image)