Mimban

The planet Mimban was inhabited by Coway, Greenies, and, Wandrella.

Secret Beginning
When the planet Mimban was developing sentinet aliens, it was the cause of mutations. Humans sent by the Secret Empire, to make the aliens terrifying, and many people would go to the Secret Empire. It also had a Mining towns, where succes fully mutated aliens were forced to take minerals, and deliver them to Imperial Ships.

Then one alien called 55-U realized that the mining technology given to them could allow a riot. While a special squad went to deactivate the Dark Troopers in the war room, a small army would distract the main army. The plan failed. Some escaped, but that battle made the Dark Empire enforce more brutality.