Powers and abilities
Evil Manta was mostly known for his use of spreading discord amongst others either with hypnosis or with telepathy. Either way, he could easily persuade others into doing as he wanted. Coupled with that, he has the ability to use electricity with his tail, enabling him to free himself from Ariel and Flounder's net.
For most of the series, Evil Manta lived up to his name, and was regarded as pure evil. He is very manipulative, even manipulating Ariel to release him from his prison in his debut. He desires power, and has wished for the trident and the Atlantican throne.
Despite his evil ways, he appears to be a good father to his son, although he does try to get Little Evil to follow in his footsteps at first. However, this also inadvertently caused him to reform.
Evil Manta is a slender manta-ray/humanoid hybrid who is muscular, thinly mustachioed (with angles sharply downward), has glowing orange eyes, plum circles under his eyes, black eyebrows, a purple upper face, lavender law, upper torso, and arms, a purple lower torso with plum abdomen, sharp black fingernails, sharp white fangs, a long black manta-ray tail, and pectoral fins (for his cape) consisting of both a black front and rose back.
It is known that Evil Manta was an embodiment of evil under the sea that spread discord and hatred throughout the kingdom of Atlantica, nearly causing it to implode with hatred. The ancient ones then confronted him and sealed him away, preventing him from causing any more terror in the waters.
For many years, Evil Manta was locked away under the sea and never allowed to be free. Unfortunately, he was unknowingly freed by King Triton's youngest daughter, Ariel, and her friend, Flounder. Once more, he began using his persuasiveness and charm to spread prejudice amongst Atlantica's population. However, Flounder and Ariel were unaffected; Flounder simply refused to listen, while Evil Manta had not yet come to Ariel. Together, the two were able to convince the other Atlanticans that they did not have to believe Evil Manta, and they were able to drive him away with their singing and happiness. Before leaving, Evil Manta vowed to get his revenge, and swore that he would take over Atlantica.
Not so long after, he then found a "powerful weapon" that Lobster Mobster discovered, a human's boot. (The boot had coincidentally appeared after a disaster, leading them to believe it was dangerous). Using this weapon, he threatened King Triton with the "weapon" in an attempt the throne of the king. Ariel was able to determine the boot's true purpose, and upon finding a pair of them, was able to bluff Manta into backing down.
It was later discovered that Evil Manta had a son, which he dubbed Little Evil. Though Evil Manta tried to raise Little Evil in the ways of villainy, Little Evil met up with and befriended Ariel, who introduced Little Evil to good. Knowing his son's mind has been filled with such thoughts by the little mermaid, he devises a plan to deal with her permanently. After trapping Ariel with a false letter from Little Evil, he unleashes a monster designed to suck out a being's ability to feel emotion, dubbed the Brain Sponge. It chased Ariel (and unknowingly Little Evil) around until they got separated. Little Evil accidentally runs into Evil Manta. He tries to get Little Evil to prove his malice by revealing Ariel's location. But knowing he could never hurt or betray her, he refused which angers Evil Manta. Unfortunately, he is suddenly attacked by the Brain Sponge (after Ariel tricked the monster into feasting on a juicy mind full of "evil schemes/imagination in order to save herself). Little Evil & Ariel quickly concocted a plan to save him. They used a vine to tie up the Brain Sponge, then preceded to remove him from Manta and crush the creature under a large boulder. Evil Manta is confused to why Ariel saved him only to find her intentions were out of pure goodness. He reforms to being good and allows Little Evil to friends with Ariel (provided Little Evil reminded him to know what's bad for him).
- A character of presumably the same species as Evil Manta and Little Evil appeared in one of the books, dealing with Ariel and Adella entering a haunted ice cavern owned by the character. The character in question resembled a vampire (specifically Dracula).