Thor (comics)
Thor, a founding member of the superhero group the Avengers, often battles his evil adoptive brother Loki, a Marvel character adapted from the Norse god of mischief. He is among Marvel's most powerful superheroes. Many recurring characters in his stories are based on Norse Mythology. Apart from this main superhero, Marvel features a number of characters based on him.
Dragon
In the Old Norse poem "Grímnismál" in the "Poetic Edda", the dragon Níðhöggr is described as gnawing on the roots of Yggdrasil, the world tree. In Norse mythology, Jörmungandr is a giant serpent that encircles the entire realm of Miðgarð in the sea around it. According to the "Gylfaginning" from the "Prose Edda", written by the thirteenth-century Icelandic mythographer Snorri Sturluson, Thor, the Norse god of thunder, once went out on a boat with the giant Hymnir to the outer sea and fished for Jörmungandr using an ox-head as bait. Thor caught the serpent and, after pulling its head out of the water, smashed it with his hammer Mjölnir. Snorri states that the blow was not fatal: "and men say that he struck its head off on the sea bed. But I think the truth to tell you is that the Miðgarð Serpent still lives and lies in the surrounding sea."