Pogona (+1 Str or +1 Con +1 wis. Pick 2)
Can hold breath for 1 hour.
Dark vision when underwater.
Cold blooded, needs to bask in a source of warmth for at least 1 hour once every 24 hours. Can bask while sleeping.
Advantage in athletics based swimming checks
advantage on acrobatics checks to balance
proficient in a natural bite attack. 1d4 piercing.