• Son (some say daughter) of Loki and Angerboda.
• Expelled by Odin and forced to encircle the earth under the oceans with its tail in its mouth (see Ouroborus).
• Causes tsunamis and storms.
• You should correct Jormangander to Jormungand .... The -er ending is a corruption of the Norse nominative case ending -r for masculine nouns. (Thank you Torfinn Ormen)

The Midgard Serpent meets Thor 3 times:

First time was in the hall of the giant Utgarda - Loki where the giant tested Thor 3x - first by having him drink his horn of mead (all the oceans), then by having him lift his cat (the Midgard Serpent in disguise), and finally by having him defeat an old woman (representing old age).

Second, Thor and Hymir, a giant, were fishing in a lake with an ox head. Suddenly, something huge grabbed the hook and a gigantic head rose from the water. Thor took up his hammer, but just as he was about to swing, Hymir got scared and cut the line, letting the creature go and disappear beneath the waves.

Many years later, on the Day of the Last Battle and the wars of god and giants, monsters and men, deity and demon, the Midgard Serpent returned to fight Thor a second time. They met on a beach and Thor immediately threw 2 thunderbolts and Jormangund gnashed its teeth. Thor took up his war hammer and brought it down on the monster's head, killing it with a mighty roar.

But Thor was not to survive the battle, either. He suffocated on the dragon's deadly breath.

• Angerboda
• Oroborus

• Book of Sea Monsters