So once upon a time Regina race were not always the big, anthro female and male. One point in their history they were primal alien creatures, similar to a T rex. They walk on digitigrade legs had a armored shell, that covered a good majority of their back, tails, and head with some located around their knees. If you notes about Regina and her race they have no eyes, that cause in their proto forms they used a frill located on the top of their heads, that would do a shake/vibrate making a sort of echo location for them to see and hunt. But once their DNA got fuck up, by an alien race their body's would have to adapt to being able to sense vibrations through the ground

This art was made by eksptt I would very much recommend you commission them on fiverr, here a link to them and samples of their work and they are all at reasonable prices.

https://www.fiverr.com/eksptt/design-a-character-or-creature-concept-art-for-you?source=order_page_summary_gig_link_title&funnel=22ad289f9ef63e5545069ac2c29eb8b1