Prior to his demise, Hrungnir engaged in a wager with Odin in which Odin staked his head betting on his horse, Sleipnir being faster than the steed of the giant's Gullfaxi[?]. After the race, which Sleipnir won, he was invited into Valhalla, but became drunk and abusive. The gods called on Thor to battle with Hrungnir, and defeated him.
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