When the builder saw that his work was not going to be completed, he resumed his giant form. When the asas thus became sure that it was really a mountain-giant that had come among them, they did not heed their oaths, but called on Thor. He came straightway, swung his hammer, Mjolner, and paid the workman his wages,—not with the sun and moon, but rather by preventing him from dwelling in Jotunheim; and this was easily done with the first blow of the hammer, which broke his skull into small pieces and sent him down to Niflhel.

- Prose Edda (The Fooling of Gylfe, XIII)