Jormungandr

Jörmungandr, also known as the Midgard Serpent, is a giant sea serpent in Norse mythology. He is a child of the trickster god Loki and the giantess Angrboða, making him a sibling of Fenrir the wolf and Hel, ruler of the realm of the dead.

According to medieval Norse sources, the gods cast Jörmungandr into the ocean that encircles Midgard. There the serpent grew so large that he encircled the world and grasped his own tail, forming a circle around the earth. The creature is associated with the sea’s perilous power and with prophecies of catastrophe.

In the events of Ragnarok, Jörmungandr rises from the ocean to face Thor in single combat. The two fight to the end; Thor eventually kills the serpent, but is poisoned by its venom and dies after taking nine steps away from the carcass. The encounter between Thor and the Midgard Serpent is one of the pivotal exchanges in the world's end-times narrative, contributing to the destruction and subsequent renewal of the cosmos.

Jörmungandr’s name is Old Norse, often rendered as “the giant one who encircles” or “world-serpent.” The figure is attested in sources such as the Prose Edda (Gylfaginning) and the Poetic Edda, and has continued to appear in modern retellings of Norse myth.