Brynhilda

Brynhilda was the alien Valkyrie in the episode “The Space Vikings.” She appeared in response to Dr. Smith using the hammer of Thor to destroy a monster, believing him to be a mighty hero. She offered Smith the opportunity to rule Valhalla in place of Thor with her. In the face of the imminent threat of the Frost Giants, she realized that Smith was not a mighty hero, and colluded in a plan to restore Thor's devastated confidence. With Thor's confidence restored, Valhalla was saved and Brynhilda and Thor reunited.