The Norse, also known as the Vikings, had a rich, colorful mythology filled with creatures of all sorts. Some - like Sleipnir, the swift, eight-legged horse belonging to the chief god, Odin, and the goats that pulled the thunder god Thor's chariot - were useful and admirable. There were also dangerous creatures - like the race of giants who hated the gods - and fearsome monsters, including a huge, scary treasure-guarding dragon.