Cheetah World

The Cheetah World was a mysterious sentient planet and home to the Cheetah People and Kitlings.

Features
The Cheetah planet had rough terrain featuring rocks and sand. Due to the Cheetah People and Kitlings living there, it was covered in bones of dead humans and other creatures in the galaxy. It had few hills and mountains in it as well and ruins of houses that a civilisation also used lay here decaying. The Planet was also described by the Master as being covered in Artron energy. (DW: Survival, NA: First Frontier)

Life Forms
The Cheetah People where the dominant species there along with the Kitlings who were used as part of their teleportation powers. They did ride horses but it remained to be seen if the horses evolved on the planet or where taken from another planet. (DW: Survival)

Sentience
The planet was in some sense, sentient and empathic and was connected to the Cheetah People. When the Cheetah People fought, the planet became unstable and started to destroy itself. The water on the planet had healing properties to the Cheetah People. The World allowed the Cheetah People to teleport to other planets to bring back prey. It also allowed people who wished to come home enough to return there by teleportation. Near-Humans such as Humans and Gallifreyans slowly began to metamorphosize, turning aggressive and physically changing into Cheetah People. The Master described the world as dying because of the aggression of its inhabitants. (DW: Survival)

History
At some point before the 20th century, an unknown civilization tried to conquer the planet. They bred the Kitlings to be their eyes and thought they could control the planet, but they were wrong. They too were turned into Cheetah People, leaving only the ruins scattered around the landscape.

During a physical struggle between the Doctor and the Master, earthquakes shook the planet, implying that it may have destroyed itself, though the Doctor told Ace that she still carried the planet inside her. (DW: Survival)