Raxas

Raxas was a resource-rich planet that was inhabited by unintelligent dinosaur-like creatures. It was later taken over by the Daleks. The story of this invasion was later recorded in Dr. Cornelius Filkins' Daleks: A History. (NOTVALID: The Battle for Raxas)

History
When the Daleks needed supplies they invaded Raxas for power for their vast ships and metal ore to make new Dalek casings. As there was no intelligent life, the Daleks incorrectly thought they could easily take it over. The Daleks only sent a small landing party to establish a mining operation.

The lead Dalek was attacked by a giant tyrannosaur that bit it in half. A second tyrannosaur crushed four other Daleks with its massive feet, before a handful of Daleks turned their disruptors on it. Even then it took repeated blasts to kill the creature.

Other Daleks were picked off by giant flying pterosaurs that grabbed them between their feet, flying high into the air and then dropping them to their deaths on the rocks below. Eventually the Daleks were able to take the planet with reinforcements. However, the planet was never safe and Dalek patrols were required at the mines to keep the dinosaurs at bay. (NOTVALID: The Battle for Raxas)