Jotun are giants in the Scandinavian mitology. It is told there are three kind of Jotuns: Hrimpursar, the Frost Giants, Eldjotnar, the Fire Giants, and Bergrisar the mountain giants. In the film Thor, there are only one kind of Jotun, Hrimpursar, the giants of frots. They live in a planet called Jotunheim, and have a power source called Casket.