Beast of the Depths

The Beast of the Depths is a monster the Trix commanded to attack the Winx Club and Daphne in the first episode of Season 6, "Inspiration of Sirenix".

Appearance
The Beast of the Depths is a giant, brown monster with spiky, yellow eyes and sharp, long teeth. It has circular, dark yellow patterns all over its body. It also has two pairs of tentacles, three pairs of feet and a spiky tail. It also has two big flippers with spikes on its sides.

Season 6
During the celebrations, the Trix command the beast to attack Daphne, the Winx and Domino's people. While Daphne is frozen with horror and despair thinking she has lost her powers and thus cannot protect her people, the Winx and the Specialists attack the beast to no avail.

Later on, the Winx convince Daphne that she can transform into her Sirenix form and will be able to drive the beast away. Daphne succeeds in transforming and commands the beast to return to the depths of the ocean.

Magical Abilities
According to Icy, it is the only thing in the Magic Dimension stronger than the Dragon's Flame. Because of its immense power, it is very durable and powerful. Although it is strong, it also has a weakness: being controlled by the power of the Nymph of Domino.

Trivia

 * The appearance of the Beast of the Depths is similar to that of the Kraken from the 2010 movie Clash of the Titans.