Incubi

thumb|Depiction of witchcraft in John William Waterhouse's painting The Magic Circle (1886)

Merlin () is a mythical figure prominently featured in the legend of King Arthur and best known as a prophet and a magician, along with several other main roles. The familiar depiction of Merlin, based on an amalgamation of historical and legendary figures, was introduced by the 12th-century Catholic cleric Geoffrey of Monmouth and then built on by the French poet Robert de Boron and prose successors in the 13th century. Geoffrey's account presented Merlin as a prophet and royal advisor to Arthur's father, Uther Pendragon.

thumb|Depiction of incubi, Vincenz Georg Kininger, 1879 An Incubus () is a male demon who is described in various folklore as appearing in the dreams of female humans in order to seduce them. Repeated interactions between an incubus and a woman will lead to sexual activity, a bond forming between them, and ultimately sexual intercourse, as he requires vaginal ejaculation discharge to survive. The establishment and perpetuation of such a relationship enables the production of a hybrid child known as a cambion, but at the expense of the woman, whose mental and physical health will deteriorate ra

1781 painting by Henry Fuseli

A vrykolakas (, pronounced ), is a harmful undead creature in Greek folklore. Similar terms such as vourkolakas (βουρκόλακας), vourvoulakas (βουρβούλακας), vorvolakas (βορβόλακας), vourvolakas (βουρβόλακας), vourdoulakas (βουρδούλακας) were also used for the creature.

nightmare creature originating in German folklore

Spirit in Russian folklore

In European mythology and literature, a cambion () is the child produced from a human–demon sexual union, typically involving an incubus or a succubus. In the word's earliest known uses, it was interchangeable with changeling.

Zburător or sburător (Romanian word meaning 'flyer') is a supernatural being in Romanian folklore, described as a "roving spirit who makes love to maidens by night".

troll-like creature from Shetland and Orkney Island folklore

thumb|150px|right|St. Augustine in a 6th-century portrait In the Gaulish language, Dusios was a divine being among the continental Celts who was identified with the god Pan of ancient Greek religion and with the gods Faunus, Inuus, Silvanus, and Incubus of ancient Roman religion. Like these deities, he might be seen as multiple in nature, and referred to in the plural (dusioi), most commonly in Latin as dusii. Although the Celtic Dusios is not described in late-antique sources independently of Greek and Roman deities, the common functionality of the others lay in their ability to impregnate an