The Æsir attacked Loki and began to hit him; Loki became frightened and said no please stop, I swear, I swear that I will find a way to make him lose his payment, no matter what.
In the evening when the master builder drove out his stallion Svadilfari to gather stones, a mare leaped out from the nearby forest. When the stallion saw the mare, he became frantic and broke free from his chains and galloped towards the mare, but the mare ran back into the forest.
The builder ran after his horse into the forest. Because the two horses ran around in the forest all that evening and night, the work on the wall was delayed.
The next morning when the master builder finally caught his horse and came out from the forest, he could see that the walls would not be finished in time, he went into a giant’s rage. Yelling and screaming, he smashed the stones and trees around him.
The Æsir now for certain realized that the master builder was a giant, so they no longer respected their oaths with him. The Æsir called upon the God Thor, who came immediately after hearing about the giant. When Thor arrived he threw his hammer Mjolnir at the giant and broke the giant’s skull into small pieces.
Because of Loki’s relations with Svadilfari, many months later, Loki gave birth to a colt, it was grey and had eight legs, this horse would become the best and fastest horse among all of the horses.