Vampire planet

A planet with an unknown name was the chosen hiding place of the King Vampire.

Development
K9 reported it had high technological prowess but the peoples were primitive. This was due to the Three Who Rule's ban on advanced technology. The scans were lilkely registering the Hydrax as the high technology. The inhabitants did have some hidden technology such as Radio transmitters. (DW: State of Decay)

Landscape
A village was the planets most prominent feature. It resembled a level 2 system. t was surrounded by forests and furthur afield were caves used by the rebels. In the centre of the village was the Hydrax, it had the appearance of a castle, rock built up around it so it appeared to be on a hill. Underneath it were caves containing the burial chamber of the King Vampire. (DW: State of Decay)

Some distance from this settlement were the lands of Zarn. His dwelling was known as the House of Zarn. There were many other village across the planet. (EDA: The Eight Doctors)

History
Fleeing the Time Lord-Vampire War, the King Vampire took the Hydrax, a human ship, as a source of blood. He then traveled into E-Space through a Charged Vacuum Emboitment and took refuge on the planet.

The King Vampire went underground beneath the Hydrax which stood vertically. Over time the Hydrax was surrounded by earth and took on the appearance of a castle. A village built up around it where villagers served the Three Who Rule who were in turn subservient to the King. (DW: State of Decay)

Visitors came from other vilages. They became infected by the vampires and returned home where they in turn infected the other residents. This process meant that most, if not all, of these outlying villages had a vampire in control. (EDA: The Eight Doctors)