I'm still not 100% sold on the colors or the markings, but here's a general idea. Excuse how cutesy my HoD-inspired style is. They're supposed to be a badass.
Hydreliox as a puppy. The presence of "adult" plumage displaying the natural coloration of the hound was the signifier that pups were ready for combat training.
Hydro would evidently escape shortly after their plumage deepened from the puppy down color.
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