A Sceadugenga, or shadow goer, is a shape-shifting creature from English folklore. Neither living nor dead, they dwell in forests, but are known to take on the forms of children and wander into villages. Sometimes, they will join families, and even forget their true nature.

Even in human form, a Sceadugenga can be identified by its black irises. Grendel, from the legend of Beowulf, has been described as a Sceadugenga.

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