Merpeople

Merpeople (also known as Mervanans) are a legendary species that are half-human (or half-duck) and half fish. Females are referred to as mermaids, while males are referred to as mermen. Merpeople tend to live in the sea within various underwater kingdoms such as Atlantica and Mervana. They are shown to coexist with sea life, with whom they are able to communicate. They are considered the most dangerous creatures in all the seas and are described as more of a threat than sharks, whales, or even a Kraken. Their powerful tails can break through wood and in large swarms they can sink ships.

They are able to pass for humans until they turn 13 when the fish physiology surfaces. The transformation is shown to be triggered by exposure to water. In addition to the fish-like tail, they also have scales on their palms and small fins that run along their forearms. They seem to possess other abilities, such as the one to generate electricity, to the point that they can fire it similarly to a defibrillator, and the one to stick to surfaces. Mermaids can also use shells as trumpets to summon and manipulate terrible storms and waves. Some mermaids have voices which are lovely enough to enchant people and lure them onto rocks.