Delta III
Delta III was the third moon of Delta Magna and refuge for the Swampies, natives of Delta Magna forced to relocate there by Humans who had colonized their original homeworld.
This moon was small, having weak gravity and a poor atmosphere, Humans had released giant squid on the moon to impress the Swampies. The moon was covered in swamps and bogs and was rich in methane. When Humans discovered this second feature, they set up refineries and attempted to exterminate the Swampies, an action move opposed by humanitarian organizations as the Sons of Earth.
- As Terran squid need salinated water to survive, Delta III probably had salt marshes.
The Doctor and Romana found the second segment of the Key to Time there, in the form of the Swampy's god Kroll. Owing to the moon's marshy terrain, which would have made it impossible for him to move about there, K-9 remained in the TARDIS and never ventured forth onto the surface of the moon. (DW: The Power of Kroll)
