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[Norse] A frost giant and father of two daughters, Gjalp and Greip. He was a bitter enemy of Thor, and having captured Loki (when Loki was flying around as a hawk) received from him a promise that he, Loki, would bring Thor to Geirrod's castle without Thor having his magic belt and magic hammer. Loki did as promised and led Thor into the trap. On the way there, though, they stopped to rest at the home of a giantess named Grid. She told Thor what was up when Loki left the room, and gave him her magic belt, iron gloves and magic staff. Needless to say Thor used each with supreme efficiency and slew Geirrod, his daughters and all other frost giants in the vicinity.

See more at Wikipedia.org...

[Norse] A frost giant and father of two daughters, Gjalp and Greip. He was a bitter enemy of Thor, and having captured Loki (when Loki was flying around as a hawk) received from him a promise that he, Loki, would bring Thor to Geirrod's castle without Thor having his magic belt and magic hammer. Loki did as promised and led Thor into the trap. On the way there, though, they stopped to rest at the home of a giantess named Grid. She told Thor what was up when Loki left the room, and gave him her magic belt, iron gloves and magic staff. Needless to say Thor used each with supreme efficiency and slew Geirrod, his daughters and all other frost giants in the vicinity.