Ratlings

The Ratlings were a humanoid race with a rodent-like appearance. They lived on the planet Zethenda, a universal rubbish dump, where they scavenged to survive. They were the last survivors of a war with the Worgoth, a powerful creature who wrought devastation across time and space.

When the Optimi arrived on Zethenda, intending to kill the Ratlings and colonise the planet, the Tenth Doctor, Martha Jones and the Ratlings activated a terraforming device that restored the planet's previous paradise landscape. This led to the Ratlings and Optimi coming to a compromise: the Ratlings would inhabit the wastelands, whilst the Optimi would live in the paradise they had been searching for. (COMIC: Waste Not)