Alim Coelacanth (1987)

Alim Coelacanth  (nicknamed Merdude by Michelangelo) is a man/fish-like creature from the lost city of Atlantis, and is also its true ruler. Merdude left Atlantis over 200 years ago in search of others of his kind - it seems that Merdude is the only mutant in the lost city.

He rescued Michelangelo from the white water rapids of the sewer.

He lost his way and the Turtles, using Donatello's Porta-Tracker, volunteered to help him find his way back home.

By the time Merdude and the Turtles arrive, Bebop, is ensconced upon the throne and issues the order to "clap them in irons", but Merdude and the TMNT disappear back into the sewers beneath the city of Atlantis.

He encounters the imprisoned Hepax Lagamina who tells him he is the true king of Atlantis and convinces Merdude to challenge Bebop to meet him in the Atlantean arena. Atlantean guards arrive and chase him and the Turtles though the sewers. Merdude uses his telepathic powers to call upon his friends of the deep who stop them.

Merdude arrives and challenges Bebop to combat. In the arena Merdude is losing until Hepax arrives and tells him to use the Trident of Power. Merdude wields the Trident of Power and Bebop quickly renounces his throne.

He chases after Shredder who stole the Star of Atlantis. Shredder blasts a hole in the city's dome and Merdue summons a giant squad to seal it.

Merdude and the Turtles get the Star of Atlantis back from the Technodrome and return it to Atlantis.

Merdude is named king and he names the young and beautiful Atlantean Hepax Lagamina as his royal councilor.

Shredder launches a counter attack with the Technodrome but Alim stops him with the Hammer of Atlantis

Trivia

 * While Merdude was a prehistoric boy mutated into a merman in the Archie Comics, this incarnation made him a deformed Atlantean (he had always resembled a fish-man).
 * His last name comics from Coelacanth, the prehistoric species of fish of which he is related.
 * He is similar to the DC Comics character Aquaman as both of them are kings of Atlantis that have mental powers over sea life

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