databank
900 year diary
sontaran invasion of gallifrey
The Doctor returned to Gallifrey announcing he was standing as President of the High Council. Once in office, he betrayed the Time Lords to the Vardans, a telepathic race capable of travelling along any kind of broadcast wavelength. In reality, the Doctor was attempting to trick them. However, once they were defeated, the Doctor learned that the Vardans were the pawns of the Sontarans who had used the Vardans' technology to invade Gallifrey and steal the secrets of time travel. The Doctor built a Demat Gun to stop the Sontaran commander Stor and without him, the invasion was foiled.