I admit i have not played Kingdom Hearts. But i have seen some lore and game play over the years on YouTube.
I had the idea recently to do my own version of an old drawing of Aqua from Kingdom Hearts having been turned into a Heartless dragoness. In other words trying to come up with my own version of the design. I still plan to do that at some point, but Instead i ended up making a generic base to build off of; usable as a ordinary enemy design. It also has its own little description;

Great Drake (Heartless Dragon)
"These Heartless form from ancient dankness left alone to fester for countless ages. They can transform to a swarm of small spheres of pure darkness, allowing them to get into places they otherwise shouldn't. They attack with their claws and tail, occasionally breathing torrents of dark fire."

Variant: Key Drake (Artificial Heartless Dragon)
"These Heartless occasionally from from the remains of fallen Key Blade wielders. Why is unknown. Differing from normal Great Drakes, they possess many additional features reminiscent of their original form. Their tail blade in particular takes after the Key Blade they once wielded, but now corrupted and incorporating the heartless symbol. Many possess strange and unique powers."


**Fan Design**: As a fan design I obviously don't own the property. So feel free to use the design if you want in your own drawings and even make up your own OCs and characters transformed into one! If you do, credit for the original design idea would be nice, though not necessary to constantly bring up.