Giant Eel

The Giant Eel is a creature that lives in the Infinite Ocean.

Overview
The Giant Eel lives in a cave near the Pillar of Control and it has a huge appetite. It appears to be omnivorous since it attempted to capture the Winx to eat them but it ate the seeds created by Flora.

Appearance
The Giant Eel looks like a giant eel with tentacle-like tendrils on its body and a large frill around its mouth. It has dirty green scaly skin like those of snakes and fish.

Season 5
After receiving a telepathic message from Daphne, Bloom told the others that they need to destroy the seal of the Pillar of Control. They head there and as they were about to get ready to destroy the seal, the giant eel that lived near it approached them, attacking them and holding them captive in its tentacles. Unable to help the others break free from its grip, Musa urgently contacts Tecna, who was currently on her date with Timmy, for help.

When Tecna arrives at the Infinite Ocean, Lithia finds her and shows her the way to Pillar of Control, as Tecna comes closer to the Pillar of Control she sees the giant eel holding her friends captive.She swims towards the monster in order to free her friends but Illiris tells her that ordinary magic does not work on it and Flora tells Tecna that it is just hungry. Tecna then leads it to the surface of the ocean, stun it with her magic and it finally releases the Winx. And in order to cure its hunger Flora uses her powers to give it food.

The Mystery of the Abyss
It makes one minor appearance at the beginning of the movie after the devourers.

Trivia

 * The appearance of the Giant Eel is similar to and might have been inspired by those of the Unagi and the Serpent from the Nickelodeon animated show Avatar: The Last Airbender.