Playable Mermaids

I think it would be cool if we could play as mermaids/sirens where creatures of the deep prefer to attack pirates instead of you and you having the ability to stay underwater for either a long time or infinitely with a downside of not being able to walk so boarding ships or going on land is an impossibility with you being able to either be a friendly mermaid that helps pirates with deliveries, hunting lost treasures or fighting the beasts of the deep and helping them not drown by pulling them up to the surface or if you want to be an evil mermaid or a siren you can puncture the hulls of ships and being able to drag sailors down to Davey Jones locker or attacking pirates directly and in general mermaids/sirens have more health then pirates with them being able to swim faster then most ships