There is a world in which dragons exist, but they are not natural as one may think, since their ancestors were artificially created.
In their chest exists still a fragment of their past: a small orb called "Core".

This sphere is a body regulator that makes sure the artificial creature is well and healthy, along with other features. Sorta like brains, these small orbs have an almost full control over the host body and allow many things to be possible.
For example, the dragons can switch between a limited amount of forms, such as anthropomorphic and quadrupedal. Of course, as seen with Kael and his Titan form, it is possible to gain new forms thanks to the help of upgrade modules, and it is where the next great use starts: These cores can be upgraded! The ancient civilisation who created such artifacts were able to build those upgrade modules that would allow the core to "edit" the body in different manners, such as adding a new form, giving the creature new abilities, and far more!

Beside the forms and the whole regulating part, the cores have a few "base" utilities, such as regeneration, which can regrow a lost limb over the weeks, and even the ability to store the soul in case of an emergency such as the death of the host.

Of course, the dragons are believed to be one of many "core species" because the Makers, those who created these cores and dragons, left clues that prove the use of such technology to create other species that now inhabit other planets, possibly building entire new civilisations and more!

It seems the Core is the highest technology in medicine and organic evolution. The ability to "safely" become anything and also perhaps even cheat Death.

But does this mean the core creatures are machines? Yes and no. Yes since all organic creatures are basically machines, and no since the core has no effect on the personality of the creature. They are still very much alive!

Nowadays, while humans keep the bones and ashes of their deceased loved ones, the artificial creatures keep these cores close to them, some often still react to the familiar presence.

And it seems a certain Ogard noticed the soft blue glow of a core in the chest of a familiar black dragon!

I was a bit tired when writing that description, so hopefully there are no mistakes or typos, but I felt it was the right time to explain the how and why to Kael's transformations (and growths). Though I am not too happy with how I wrote it. I should write only when I feel inspired.
I might also stop writing these long texts because it's better to let the viewer imagine by themselves. We all create our own story after all! It's the magic of art.

A big thank to  artisipancake for the picture! ^^

Original here! https://www.furaffinity.net/view/28685017/

Art & Ogard (Orange Dragon) ©  artisipancake
Kael Artherion (Black Dragon) ©  artherion