PHOTINO BIRDS

Photino birds are a supersymetric species of dark matter entities that inhabit the gravity wells of stars. With multi-billion year life span and the ability to travel faster than the speed of light. It is theorized that they began their civilization shortly after the birth of the universe and the beginning of stellar evolution. Being dependant upon stars for their breeding grounds, when the first stars of the universe began showing instabilities such as supernovae, they set out to correct these instabilities by accelerating steller evolution throughout the universe. The end result would be a stable universe dotted with white dwarfs. This make life impossible for most planetbound life forms. Upon discovering them, the Xeelee species, one of the most advanced in the universe, started fighting them until they realised this war to be unwinable and decided instead to start moving to other universes.The Photino birds hardly know about other existing life-forms with the exception of the Xeelee.
To fight the Xeelee, the photino birds have developped means to use galaxies as weapons and to propel them to near lightspeed. Photino Birds share the awareness and memories of their parents and ancestry, as each bird is actually an exact copy of its parent
Source: Stephen Baxter, Xeelee Sequence.

XEELEE

The Xeelee are a hyper-advanced civilization which has existed for billions of years whose technology far exceeds that of almost any other known species. They are spread across the universe, typically being concentrated in the heart of galaxies whose black holes they use.
They have also spread gigantic artifacts and huge inscrutable structures throughout space. The most notable of those being the Ring, AKA The Great Attractor, a huge construct drawing in galaxies for millions of light years around with its awesome gravitational well. The Ring, devised to tear a hole in the universe and open a portal to parallel universes, is to be used as an "escape hatch", if the Xeelee were to end up being unable to stop the Photino Birds from aging the stars of the universe.
Hypothetical letterature speculates that Humanity might in the future encounter the Xeelee and begin to war with the Xeelee, which is most likely to last over ten thousand years and to be lost by humanity in the end.
Source: Stephen Baxter, Xeelee Sequence.

CELESTIALS

The Celestials appear as silent, massively powerful humanoid armored forms with an average height of 2000 feet. Little is known regarding their appearance underneath the armor. Some believe it to only be a shell for beings of pure energy, so as to allow interaction with the physical world. It has been suggested that they may even be sentient stars. Their origin as their numbers remains a mystery as only a handful have ever been seen.

They travel the universe with an agenda of genetic engineering of younger species.

On Earth, they are apparentlt responsible for modifiying humanity in three offshoots, the Eternals, the Deviants and the Latents (representing most of the population), over a million years ago. The exact reason for the Celestials' genetic manipulation of proto-humans is unknown, although it is known that the Celestials conduct similar experiments on other races such as the Skrulls.

Each race that the Celestials has experimented on is periodically assessed by Arishem the Judge, and if a race "fails" by Celestials standards, he sends Exitar the Exterminator, a 20,000 foot tall Celestial to carry out the sentence. Sentences can go from the terraforming of a planet into a garden paradise, with part of the inhabitants being destroyed, and the survivors being given a second chance to the destruction of a planet along with its population. The Celestials policy of interference is the exact opposite of the Watchers policy of observation, and the two races have been enemies for many eons.

Source: Marvel Universe “The Eternals”

WATCHERS

Planet of Origin : Unknown

The Watchers were among the first planetbound intelligent humanoid species in the universe. The Watchers are led by a Watcher known as the One, who is physically far, far larger than the other Watchers and who serves as a repository for all data and records into which the other Watchers upload all the information they collect,.

They started with the belief that their knowledge belonged to the universe, and so decided to share it with other younger species. They came to the planet Prosilicus, interfering with their evolutionary and technological development. Despite the well-intentioned actions of the Watchers, the species self-destructed in nuclear warfare. Horrified, the Watchers swore a vow of non-interference they’ve maintained for millions of years and, leaving their homeworld, dispersed throughout the cosmos for observation purposes.

The Watchers possess the ability to manipulate reality at will, at least on a local level, can teleport themselves almost anywhere in the Universe instantaneously. They appear to be able to either simultaneously watch multiple Universes and Dimensions or to be in more than one place at the same time, and possess vast mental, physical, and energy-manipulating powers. They can also alter their shape and increase and decrease their size at will. There appear to be no secondary sex differences between male and female Watchers. Even if rarely, Watchers still reproduce sexually, however, and rudimentary family relationships still provide care and training for their young.

The Celestials are of comparable age and power to the Watchers. But their agenda of genetic engineering of younger species is in direct opposition to the Watcher agenda of non-interference. The two species have thus been engaged in conflict for billions of years, a conflict that culminated fairly recently in1995 and was not resolved one way or the other.

Source : Marvel Universe « Fantastic Four #13 (April 1963) »

MALTUSIANS / OANS / GUARDIANS OF THE UNIVERSE

Planet of origin: Maltus

Maltus was among the first planets on which planetbound humanoid sentient life evolved. It happened very similarly to Earth. The planet had it's era of dinosaur-like creatures previous to a humanoid race. Along with the humanoids, another organism, the symbiotes, sprung up. The microscopic ymbiotes merged with the humanoids and gave them their advanced intellect, a proactive immunity system along with the building blocks to immortality. They were the source of all the powers granted to the race of humanoids that eventually evolved into the Guardians of the Universe.

Physically. they started as tall dark blue humanoids with black hair. Males and females drifted apart after a plague whose virus was only avtice in the presence of both sex. Even though the virus was eliminated , males and females remained apart during millions of years but have recently reunited. In the meantime, they evolved into short 4 feet tall, large-headed, white-haired pale blue superintelligent functionnally immortal dwarfs with vast psionic power such as Cosmic energy manipulation, telepathy and telekinesis.

Some 4 billions years ago, they left their homewrold to reeastablish on Oa, and shortly after, learned how to manipulate the energy they called "the Glow", the collective willpower of the inhabitants of the universe and eventually created a Central Battery to store it. This gave the Guardians an ultimate tool to pursue their goal of shaping an orderly universe.

An army of robots called Manhunters was created to patrol the Universe. They rebelled and were exiled. After this failed experiment, they invented the Green Glob, an intelligent teaching machine, programmed to educate mortals all over the universe and able to briefly alter reality to do so.

Then came the short-lived Halla's, an intergalactic police corps wielding power guns chanelling the Glow energy, wich paved the way for the Green Lantern Corps. These troops were given some of the power of the Central Battery, accessed through a ring.

Source : DC Universe « Green Lantern Vol. 2 #1 (July 1960)”, “Secret Origins #23”