Thor Slay Hymir

It is said that then the giant Hymir changed colour, went
pale, and panicked when he saw the serpent and how the sea
flowed out and in over the boat. And just at the moment when
Thor was grasping his hammer and lifting it in the air, the giant
fumbled at his bait-knife and cut Thor’s line from the gunwale,
and the serpent sank into the sea. But Thor threw his hammer
after it, and they say that he struck off its head by the sea-bed. But
I think in fact the contrary is correct to report to you that the
Midgard serpent lives still and lies in the encircling sea. But Thor
swung his fist and struck at Hymir’s ear so that he plunged
overboard and one could see the soles of his feet. But Thor waded
ashore.’

Then spoke Gangleri: ‘Have any greater events taken place
among the Æsir? It was a very great exploit that Thor achieved on
this expedition.’


- Prose Edda, Gylfaginning