Promethea is one of the planets you will be visiting in Borderlands 3. It’s the home to the Atlas corporation headquarters. The planet is a metropolitan world covered in futuristic towers of chrome and glass. A recent siege by Maliwan has turned the urban environment into a warzone; their mechanized infantry patrol the streets, rodent/insect hybrids known as Ratches infest the sewers and back-alleys, and the Children of the Vault are seizing the opportunity to recruit displaced and disgruntled citizens. Atlas CEO Rhys Strongfork is getting desperate.
Promethea is also the planet where the Atlas Corporation opened the first Vault. They found the Eridian technology with the help of Typhon Deleon, the first Vault Hunter. While Typhon went his own way the Atlas Corporation reverse-engineered the alien technology. With this, they were able to manufacture improved starships and weaponry.