Ectoplasm Specter

The Ectoplasm Specters are legendary creatures in Forest of Flowers, Gardenia, Earth.

History
According to the Legendarium, they used to haunt the Forest of Flowers. They appear after a gust of wind arrives. They are also violent spirits. The Ectoplasm Specters are mentioned in the Legendarium:

"Once upon a time, the Forest of Flowers was haunted by a malevolent force."

Appearance
They are ghost-like figures that have pale white hands. Their lower body part is green and looks like the those of spirits. They wear purple cloaks, which covers their face, so only a green, shadow-like substance can be seen.

Season 6
In "The Fairy Godmother", when the Trix are about to lose in the battle with Winx in the Forest of Flowers, Selina summons the Ectoplasm Specters to attack the Winx. The Winx cannot fight them because the can become untouchable and appear in another place. However, when they are about the destroy the Winx, Eldora tells another legend of the Forest of Flowers to use the flowers' power, which defeats the Ectoplasm Specters.

In "Mythix", they appear in the flashback while Eldora is talking about the Legendarium.

Magical Abilities
The Ectoplasm Specters are malevolent ghosts that have the abilities of spirits, which include intangibility. They are able to shoot painful, green rays of energy to fight against their enemies. They can also teleport from one place to another quickly. They can instantly regenerate with ease, when they are hit.

Weakness
The Ectoplasm Specters have only one known weakness: the power of the Lenugia in the Forest of Flowers. When the power of the flowers hits them, they instantly disappear.

Trivia

 * Specters are dead spirits, it is unknown who were they when they were alive.
 * Ectoplasm is a substance or spiritual energy believed to be exteriorized by mediums.
 * More popularly, Ectoplasm is a slimy green substance produced by paranormal beings from the Ghostbusters franchise.
 * The appearance of the Ectoplasm Specters is similar to that of Dementors from Harry Potter
 * These specters are similar to Mantocefalus in Season 5: they both cannot be hit easily, and they both can disappear and appear again, along with teleporting themselves.