Hrungir (Old Norse: Hrungir) is a giant described in Skáldskaparmál as the mightiest of all jötnar, killed by Thor in single combat. The episode begins when Odin races Hrungir on horseback; Hrungir, pursuing Odin, inadvertently gallops through the gates of Ásgarðr and is invited to drink with the gods, where he becomes boastful and threatening. The gods summon Thor, who challenges Hrungir to single combat.

Hrungir has a head and heart of stone and carries a whetstone as a weapon. In the duel, Thor hurls Mjölnir while Hrungir throws the whetstone. They collide mid-air, the whetstone shatters, and a fragment lodges in Thor’s head. Mjölnir shatters Hrungir’s skull. One of Hrungir’s legs falls across Thor’s neck, pinning him, and only Thor’s young son Magni is strong enough to lift it.

The episode has skaldic corroboration in the ninth-century Þórsdrápa by Eilífr Goðrúnarson, providing early independent attestation. The whetstone fragment lodged in Thor’s head is referenced in Hávamál (st. 155) as an object whose dislodging Odin knows a charm for.