I finally finished the species sheet of my babies. I needed to cut the image in pieces so it was easier to read on Tumblr. But you have the full image here.

Be aware this is a closed species of mine! 
I made the concept and all and it is not open for other people to do their own without my permission! Sorry! 

Information about them:

General desc:
The OXAs are a ancient species of independent long-lasting beings that live in the void of space. They have no need to consume any type of gas since their ‘hearts’ are cores of energy in their back that trails down in the form of a spine. This means their bodies are manufactured energy this core is able to produce. 
These creatures live off energy, mostly light. And that is where their 'feathers’ take into place, these are some sort of natural energy panel their bodies have where the light around them is absorbed in a daily basis. 
Even though they constantly drain light, sometimes this is not enough to power up their bodies which have and need a massive amount of energy to survive. This happens in galaxies where 'something’ is eating the stars. The only way of surviving they have is to eat each other. 
In dying galaxies the adults eat the younglings and elders for two reasons, they want to avoid another mouth to feed and they are so desperate they resort to that.
Their second and less used way to feed is by using the tendrils that their bodies have and consuming material, turning it into fuel for their cores. This material can be anything that has any sort of energy, meat, crystals, water, etc. They often use this mechanism when they are residing in planets.
There are four ways a oxa can be killed; By being eaten by another one, being sucked into a black hole, starving because of lack of light and anti-matter.

The Society: 
The OXAs as a society reached a point they barely need to interact with each other anymore since their roles are already clear. This often ends up with oxas fighting with each other when they argue since they have long since forgotten how manners work. 
The amount of 'feathers’ these creatures have and their color often divide them into classes. By tradition the lower classes need to respect and obey their higher beings, this is a instinct thing mostly since higher beings are often higher because they are more powerful, in a duel the lower class oxa would lose. 
These creatures are very intelligent due to their age but not at all socially intelligent (is that a term?) They are old, wise but never really stay in another society other than theirs for too long. This is why when they go down to a planet to do their job, they tend to take a long time to adapt and to know how the planet works, it is always all new to them. 

The life Cycle: 
Young: Oxas are born off the Galaxies’ royal elders. Kind of in a Queen Bee mechanism sort of thing. 
These are often stored inside large rocks in space hidden from adults that will probably try to eat them. Younglings are small in size and only have one core developed inside of them. Which means they are very weak.
Their tint is ALWAYS a cold blue tone which turns into green slowly when they reach their young adult phase. 
Younglings are mentored by the Royal’s most trusted elders which teach the youngling the basics of their society and how to fight for themselves. When this elder is dying they often give their body to the younglings to consume and grow stronger. 

Adult: An adult Oxa with green feathers pretty much means one that can fight and work for themselves. This is where they separate themselves from any other oxa and go to work on their species’ mission of being warriors that start and end wars to keep a balance. The adult Oxas are the one that infiltrate planets in search for either stop something going on in it or eat its core.
Depending on the galaxy they are from they have different power levels due to the presence of stars in each, a adult from a weak galaxy will be weak and mostly corrupted. One from a good galaxy will be noble and stainless. 

Elders: There are two types of elders, the Royal Elders which manage the galaxy they are in and the normal elders. Normal elders are often highly respected because they are survivors and very often war veterans. Non-corrupted elders are very rare and are often the ones that look after younglings since they can confirm they won’t consume them. 
Every elder reach a point their bodies start losing color and showing black stains on their skin, the amount of corruption they have states how soon this happens. These creatures live a long time but were not made to be timeless so after a long time their cores die out and them along with it.

This is what i am gonna write so far, if you have any questions feel free to send in an ask!