Gwyllion

Gwyllion or gwyllon (plural noun from the singular Gwyll or (Yr) Wyll "twilight, gloaming") is a Welsh word with a wide range of possible meanings including "ghosts, spirits" and "night-wanderers (human or supernatural) up to no good, outlaws of the wild." Gwyllion is only one of a number of words with these or similar meanings in Welsh. It is a comparatively recent word coined inadvertently in the seventeenth century by the Welsh lexicographer Dr John Davies (Mallwyd). They may also be known as mountain fey, fae, or fairies.

One account of a species of gwyllion refers to them as ugly female spirits wearing ash-colored clothing and an oblong four-pointed hat, carrying a pot in one hand. They also are known by their disturbing laughter and their cries of "Wb!" They are said to live in mountainous areas and love to mislead or scare travellers. However, if one of these gwyllion in disguise enters your home and is treated right, it is believed they will do no harm. These gwyllion are repelled by metal knives, and a flash of a knife is thought to be enough to send them away.

The Gwyllion is featured as the main antagonist in 2013 CGI animated film Barbie: Mariposa and the Fairy Princess. She appears as a vengeful old woman with light grey hair who attacked the crystal fairies.

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