Deepworlder

ability score increase: When determining your character’s ability scores, increase one score by 2 and increase a different score by 1, or increase three different scores by 1. You can't raise any of your scores above 20.

age: Surface Deepworlders live up to 200 years, while those from the deeper levels may gradually live up to 500.

Size: Medium

speed: 30ft (swimming speed is equal to your walking speed)

Languages: Common, Aquatic

race features:
Child of the Sea. You can breathe air and water, and you have resistance to cold damage.
Darkvision. 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 discern colors in that darkness only as shades of gray.
Friend of the Sea. Aquatic animals have an extraordinary affinity with your people. You can communicate simple ideas to any Beast that has a swimming speed. It can understand your words, though you have no special ability to understand it in return.
Keen Senses. You have proficiency in the Perception skill.