In Norse and Germanic mythology, Fáfnir (Old Norse: Old Norse pronunciation: [ˈfɑːvnez̠]) is a mighty dwarf and son of Hreidmar, and brother of Regin and Ótr. Once cursed by Andvari's ring and gold, Fafnir slays his father out of greed and becomes a dragon. Fafnir's brother Regin assisted Sigurd in obtaining Gram, the sword he used to kill Fáfnir.