Mökkurkálfi- Norse GiantGiant

The Duel at Grjótúnagarðar

Hrungnir, the mightiest of the jötnar, had been tricked into a horse race with Odin and ended up in Ásgarðr, where the gods reluctantly hosted him. When Hrungnir grew drunk and belligerent, boasting he would sink Ásgarðr into the sea and carry off Freyja and Sif, Thor was summoned. A duel was arranged at the boundary of the jötunn's territory, at a place called Grjótúnagarðar.

The jötnar realized that if Hrungnir fell to Thor, the rest of them would fare badly. They decided to build a champion to stand beside their warrior. They constructed Mökkurkálfi from clay, making him nine leagues tall and three leagues across the chest. But they could not find a giant's heart large enough to animate such a body, so they placed a mare's heart inside the clay form instead. It gave Mökkurkálfi life of a sort, but no courage.

When Thor arrived with his servant Þjálfi, the clay giant trembled with fear. Þjálfi ran ahead and told Hrungnir that Thor was approaching from below ground, tricking the stone giant into standing on his own shield. While Thor engaged Hrungnir directly, hurling Mjölnir to shatter the stone giant's skull even as Hrungnir's whetstone lodged in Thor's own head, Þjálfi simply knocked Mökkurkálfi over. The clay giant fell without a fight. The mare's heart had nothing to give.