Your constitution increases by 2 and your wisdom increases by 1

Age is just a construct to them, the age of fathom lungs are mysterious and obscure they have been recorded living for hundreds of years.

You speak common and abyssal

Fathomlings on land are pushing 7-8 ft in height but their try length when see underwater is around 10-11 ft

You may breath air and water

You have been in the darkness for so long. It has become comfortable and you can see anywhere now. You have blindsight up to 30ft.

You are incredibly unnerving to look at. You have advantage on intimidation checks.

You float along till your prey is within reach. You have 30ft swim speed

The abyss has warped you into a greater and better thing. Choose two adaptations that you deem fit for your character