Green Lantern Corps

Some 3 billion years ago, natives of the overpopulated planet Maltus evolved into immortals of great power. They subsequently settled the planet Oa and declared themselves the Guardians of the Universe and enemies of evil after one of their own, the renegade scientist Krona, performed a forbidden experiment that had terrible consequences for the Universe at large.

After a few trial and errors, the Guardians decided that their newest force of soldiers for good would consist of living beings, ones who had free will and strong moral character.

To arm this new legion of celestial knights, the Guardians created the Power Rings, rings of inconceivably-advanced technology that allowed their wearers to project green beams of energy with which the bearer could conjure objects of any size or shape, limited only by his or her imagination and willpower.

This eventually led to the formation of the Green Lantern Corps.

They patrol different sectors of space as Intergalactic Space Patrolman.