Accustomed to the Deepest and Darkest depths of the ocean, you have superior vision in dark and dim conditions. You can see in dim light within 60 feet of you as if it were bright light, and in darkness as if it were dim light. You can’t discern colour in darkness, only shades of Blue.

Atlings don’t need to sleep. Instead, they meditate deeply, remaining semiconscious, for 4 hours a day. (The Common word for such meditation is “trance.”) While meditating, you can dream after a fashion; such dreams are actually mental exercises that have become reflexive through years of practice. After resting in this way, you gain the same benefit that a human does from 8 hours of sleep.

Atlings Being half Axolotl Have Feathery external gills in which they can breathe underwater with, It also doesn't matter which type of water either since you have adapted to that

Atlings have adapted to underwater environments so much so that they can swim at double or even triple the speed of normal beings.

Being half Cold Blooded, you are resistant to any kind of cold damage