Regin

Reginn, often Anglicized as Regin or Regan, in Norse mythology, was the son of Hreiðmarr and foster father of Sigurd. His brothers are Fafnir and Ótr. When Loki mistakenly kills Ótr, Hreiðmarr demands to be repaid with the amount of gold it takes to fill Ótr's skin and cover the outside. Loki takes this gold from the dwarf Andvari, who curses it and especially the ring Andvaranaut. Fafnir kills his father for this gold, but eventually becomes a greedy dragon. Reginn gets none of the gold, but he becomes smith to the king, and foster father to Sigurd, teaching him many languages as well as sports, chess, and runes.

Reginn had all wisdom and deftness of hand. Of his two brothers, he has the ability to work iron as well as silver and gold and he makes many beautiful and useful things. While Sigurd is living with Reginn, Reginn challenges Sigurd's respect in the kingdom. He tells Sigurd to ask for a horse. Sigurd asks the advice of an old man in the forest, and the old man shows him how to get a horse that is descended from Sleipnir, the eight legged horse of Odin. Reginn continues to goad Sigurd, this time into killing Reginn's brother Fafnir. He offers to make a sword for Sigurd, but Sigurd broke every sword Reginn forged for him by striking at an anvil. Sigurd retrieves the broken pieces of his father Sigmund's sword, Gram, and brings them to Reginn. Reginn repairs the sword and gives it back to Sigurd. When Sigurd again tests the blade by striking the anvil, the anvil this time is split down to its base, and when Sigurd places a piece of wool in a stream, the current pushing the wool against the sword was enough to cause the blade to cut it in two. Sigurd is finally very pleased with Reginn's repaired weapon.

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