The lost civilization was a culture that lived below the surface of the planet Preplanis for over a thousand generations. They were a race of conquerors, and bred an army as an invasion force for their plan to take over the entire universe. The people were led by a young Princess who slept on a tuffett, awaiting the kiss of a visitor from another world. The home planet of whoever awoke the princess would be the first target of the invasion. (The Lost Civilization)
Background[]
The lost civilization was not named in the episode.