Oans (Earth-5180)

"We are immortal. We are the Guardians of the Universe. We can do whatever we like."

- - Guardians of the Universe

The Oans, also known as the Guardians of the Universe, are an ancient sapient race of small blue humanoids with vast strength of Willpower who act as the leaders of the Green Lantern Corps, an interstellar peace keeping force. "Guardians of the Universe" is simply the name the species bestow upon themselves as peacekeepers of the Corps, their true name and ancient origins having been long forgotten through time.

Early History
The Oans settled on Oa after escaping from their planet's destruction at the hands of the Celestials. On Oa, they found about the Emotional Electromagnetic Spectrum, an energy which could manifest in eight forms: Willpower, Fear, Rage, Compassion, Avarice, Love, Life, and Death. The planet in particular was rich with Willpower, manifested through a green light, and so the Oans decided to harness it with their advanced technology.

Parallax and the Manhunters
However, the Oans also found about Fear, manifested through a yellow light. They did not dare to risk succumbing to Fear, as they knew it could shape even their most beloved ones into something they couldn't recognize. One of them, Krona, however, sought to manipulate the energy, as he though it could serve as a better weapon for them to use against any threat. When he attempted to use it, the yellow energy absorbed him and transformed Krona into a being made of Fear itself known as Parallax.

The Oans assembled themselves and managed to defeat Parallax, banishing him to a frozen planet at the edges of the Milky Way galaxy. Seeing the power they had, the Oans named themselves Guardians of the Universe, and started using the energy of Willpower to power the Sentinels, a race of robotic beings that would serve as the Guardians' own police peace-keeping force through the galaxy.