Fáfnir
In Old Norse, Frænir, is a son of the drawf king Hreidmar and brother of Regin, Ótr, Lyngheiðr, and Lofnheiðr. He is affected by the curse of Andvari's ring and gold, turning into a dragon out of greed. Fáfnir is later slain in the Icelandic Volsunga Saga by Sigurd. The heart of Fáfnir, eaten by Sigurd, grants him the ability to commune with birds.