Grimhild

In Norse mythology, Grimhild or Grímhildr (masked battle) was a beautiful but evil woman. She was married to king Gjúki, of southern Rhine, Burgundy. She had three sons, Gunnarr, Hǫgni and Guttormr, and a daughter, Gudrun. She was the sorceress who gave Sigurðr a magic potion that made him forget that he ever married his wife Brynhildr, so that he would marry Gudrun, her daughter. But she did not stop there. She wanted her son Gunnar to marry Brynhildr, but she refused to marry him, and she would only marry the man who could cross the ring of flames she put up around herself. So Grímhildr talked Sigurðr into helping Gunnarr marry Brynhildr. Since Sigurðr was the only one who could cross the flames he and Gunnarr switched bodies, so Gunnar's body could cross the flames. Brynhildr then married Gunnar, because she made a promise. When Brynhildr learned that Sigurðr had betrayed her with another woman (Gudrun), not knowing he had been bewitched into doing so by Grímhild, she was out to get revenge. She ended up killing Sigurð and herself by the end of the saga. Grímhildr then made Gudrun marry Brynhild's brother Atli. Gudrun didn't want to marry him because she knew he would end up killing her brothers. This is the last that we hear of Grímhild in the Völsunga saga; it is probable that the ring's curse also brings misfortune and even death upon Grímhild herself.