Vaycaylians were Merfolk native to The Gulf of Melange. Being merpeople, they had the ability to breathe both air and underwater.
Their top halves were humanlike with aquatic features, while their bottom halves were dolphin-like tails. It was extremely difficult to differentiate males and females.
They were led by a Mer-King or Mer-Queen.
They had an underwater city on Spinner Cay with a few access points for communication with normal humans.
Long ago, they had been land dwellers too, but at some point decided to go back to the waters.