Mastarpi

Age, Mastarpi live for around 90-100 years, reaching adulthood around the age of 21.
Size, Mastarpi stand around 5-6ft tall. Your size is medium.
Speed, your base walking speed is 30 feet and you have a swim speed of 60ft
Amphibious, you can breathe underwater without issue.
Bioluminescent, once per short or long rest, as a bonus action you can generate a 20ft aura of bright light and a further 20ft of dim light. This lasts for 1 hour or until you end it as a free action.
Charged Tail, your tail counts as a natural weapon with a range of 5ft dealing 1d6 Piercing damage + 1d4 lighting damage.
Eclectically charged, as an action you can target a creature within 15ft, sending out a bolt of electricity, forcing them to make a CON save (Dc = 8 + Proficiency bonus + Constitution modifier) or take 2d6 lightning damage or half as much on a successful one. the bolt then arcs to the nearest enemy within 10ft forcing them to make the same save, the bolt arcs a number of times equal to you proficiency bonus. You may use this trait a number of times equal to your proficiency bonus, recharging all spent uses after a long rest.
Languages, you can speak, read, and write Common and once other language of your choice.