Witches are magical creatures of the magic dimension and are the magical opposite of Fairies. Witches and wizards are similar in appearance to humans and Fairies. However the source of their magical powers is from their negative feelings and from darkness, while that of the Fairies is from their good feelings and from light. This reflects itself in the dark clothing, punk-like and gothic-like of the Witches.
Even if some witches have used their powers for evil purposes, most witches are not necessarily evil as has been mentioned several times in the series, examples being Miss Griffin who helped the Company of Light fight the Ancestral Witches (as an effort at redemption for having initially worked with the Ancestresses and Valtor, though it was mentioned by Valtor that Griffin and Faragonda were already friends when Griffin was still with the Ancestresses when he says that Griffin left the Ancestresses to side with her "great friend" Faragonda), Miss Faragonda (who was a Witch but later became a Fairy), Mirta, Lucy and the many other Witches of Cloud Tower who helped the Fairies against the Trix, Lord Darkar (unsuccessfully due to their rivalry with the Fairies) and Valtor many times.
Lucy once even told Mirta that not all witches were evil like the Trix, and that some are strong and proud, like Miss Griffin, whom she considered as a role model.
In the Shaab Stone arc of the Winx Club Comic Series, Miss Griffin says that both witches and fairies fight evil, but while fairies use good magic, witches use bad/dark magic (witchcraft).
Witches also kidnap and eat small children, as in the case of Bony-Legs.
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