Grinhilda the ValkyrieEditGrinhilda was the leader of the Valkyries, and Odin's ex-lover during Xena's dark days. She didn't trust Xena when she joined the Valkyries, and when Xena went after the Rheingold, Grinhilda took the other Valkyries to stop her. None of them could stand up to Xena though. She killed most of them, and defeated Grinhilda.
Grinhilda came back to fight Xena once she turned the Rheingold into a ring. Grinhilda put on the ring to use against her, but was turned into a monster before she could kill her.
36 years later when she was turned back into a human, she didn't age at all, and Xena brought her back to Valhalla. She forced Odin to make her the leader of the Valkyries again, so she could use them for good.When Aphrodite was made mortal, Grinhilda had Nigel the new reporter find her and bring her to Valhalla where Xena could make her a goddess again.
Grinhilda the MonsterEditUsing the Rheingold ring against Xena cursed Grinhilda. It took away her beauty and humanity. Xena cut off her finger so she could get the ring, but Grinhilda still had godly strength. Xena trapped her in a mine shaft using a lock from Odin that was suppose to last forever. Grinhilda was pregnant when she turned into a monster, and gave birth to the monster Grendel. Sometime between when she was trapped, and when Xena came back 35 years later, the lock broke, and Grendel got out.
Xena killed Grendel thinking it was Grinhilda, and came after Xena even madder at her than before. Grinhilda, Odin, Waltraute, teamed up on Xena, and forced her to use the ring. Xena defeated them, and Gabrielle was given the ring and protected by Brunhilda's eternal flame. While Xena's memories were lost for a year, Grinhilda guarded the Rheingold. Xena finally came back, and got the ring back from Gabrielle. She used it on Grinhilda, and turned her back into a human.