One of the strangest moments in Thor history came when he was transformed into a frog by Loki. This wasn't just a one off either as celebrated Thor writer Walter Simonson kept the God of Thunder this way for a total of four issues. During the course of this story, Thor even ended up leading a clan of frogs into battle against a villainous horde of rats. He did eventually return to Asgard to reclaim his old form, but not before leaving a shard of Mjolnir for his ally Puddlegulp. That frog would go on to be transformed into Throg (yes, really) and now wields a very tiny version of Thor's hammer as a member of the Pet Avengers.