Giant Eel (SpongeBob SquarePants)

This giant eel appeared in a 2004 Nickelodeon film, The SpongeBob SquarPants Movie.

Overview
It is described as a massive, dragon-like, purplish-black eel who has red eyes, purple antennas, and pink dots on its head, and a yellow fin located on its back.

It made a brief appearance in the film, where it ate a Frog fish, while it chased Spongebob and Patrick. It also ate their vehicle, the Patty Wagon.