Ragnarok: The fabled end of the world, when giants, monsters, and Norse gods battle for the future. The gods were winning until the great serpent Jörmungandr emerged. It swallowed Valhalla and contorted itself across the land. Odin has just enough power to strike with one final bolt of lightning, and you have the fabled hammer, Mjölnir. Can you two destroy the serpent? Dan Finkel shows how.