Homebrew
Shalarin are hairless humanoids with smooth skin like that of a dolphin. They are the same general shape as elves. Both genders are generally around 6 feet (1.8 meters) tall, with elongated fingers and toes and webbing between the digits. Most adult shalarin have a lighter-colored dorsal fin that rises from the bridge of their nose back across their skull and down their spine to their tailbone. The tip of the fin is up to 1 foot (0.3 meters) on top of their head and can fan out for 2 feet (0.61 meters) behind them at the shoulder. Colored markings on it clearly indicate the caste to which an individual belongs. Should a shalarin become a magic user, the fins and webbing take on a permanent glow. While most shalarin are a silvery color, they can also be a wide range of other colors including ivory, red, orange, midnight blue, or jade. Bronze is noted to be an unusual and highly attractive coloration. Their eyes are dark and have no irises.
Like most aquatic races, shalarin rarely wear clothes because of the drag it creates while swimming. Most wear nothing more than a belt or harness made of woven kelp, sea snake skin, or eelskin. These are used to carry necessary weapons or equipment. Shalarin nobles will sometimes wear clothes while at court as a mark of status, but these are generally very sheer and silky.
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. While underwater you can see in dim light within 120 feet of you as if it were bright light, and in darkness as if it were dim light. You can't discern color in darkness, only shades of grey.
Telekinetic Reprisal. When you take damage from a creature that is within 10 feet of you, you can use your reaction to emanate telekinetic energy. The creature that dealt damage to you must make a Strength saving throw (DC equals 8 + your proficiency bonus + the ability modifier of the score increased by this feat). On a failed save, the creature takes 2d8 force damage and is pushed up to 10 feet away from you. On a successful save, the creature takes half as much damage and isn't pushed. You can use this reaction a number of times equal to your proficiency bonus, and you regain all expended uses when you finish a long rest.
Amphibious. You can breathe both air and water.
Underwater Capability. Underwater combat does not impose any penalties or disadvantages on movement or weapon attacks.