Originally  PinLe prepared some sketches for me for mountable beasts some years ago.

Here are the finished designs.

Yy, the middle sister.

Uu, the youngest sister.

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As denoted by the antlers on their head, the scent they bear and the aura they radiate, the Eldkin are special Beastkin from an ancient age. They are special guardians that Mother Nature cares for.

Yyu currently works for The Labs, though they are very careful around their scientists and workers due to their background and corruption. Yyu's body is able to withstand any form of pressure in the depths of the sea, making her a wondrous scout and retrieval unit.

Yyu hates The Labs, as they are filled with maniacal scientists and doctors who experiment on just about anything that they can get their hands on. But due to a debt Mother Nature has to their country, she must stay just a little longer until she can safely return home. She has two twin sisters waiting back home.