Vitki (from Old Norse: Wise one, pl. vitkar) was a sorcerer and magician in Norse Heathen societies. A Vitki could be men and women, experts in the tradition of Magic Runes, knowledge of the runes and healing ability as healers. A Vitki was a shamanic figure during the pre-Christian medieval Scandinavia, sometimes compared to prophets and oracles. The vitkar could carry tattooed on their chests hugrúnar (runes to memory and loquacity). Currently there's a Vitki figure in Germanic neopaganism.
Norse sagas
The Norse sagas are testimonies of various methods of runic spells as well as good fortune divination techniques and practices that required the intervention of vitkar and völvas:
There were other less successful spells more related to the necromancy and is used to alter the lives of others as Myrkirstafir (dark marks), Bölstafir (evil marks) and Flaerstafir (brands of misfortune). In Old English the term Beadurun (Rune of conflicts) that was used clandestinely to wish misfortune. Many of these runes and spells are mentioned in Sigrdrífumál, although no other medieval evidence is giving support the existence of such magical signs.