Regin

thumb|Sigurd killing Regin in an engraving from the Hylestad Stave Church thumb|The decapitated Regin in the Ramsund carving In Norse mythology, Reginn (; often anglicized as Regin or Regan) is a son of Hreiðmarr and the foster father of Sigurð. His brothers are Fáfnir and Ótr.

Reginn goads Sigurð into killing Reginn's brother Fáfnir. He offers to make a sword for Sigurð, but Sigurð broke every sword Reginn forged for him by striking at an anvil. Sigurð 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 Sigurð. When Sigurð again tests the blade by striking the anvil, the anvil this time is split down to its base, and when Sigurð 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. Sigurð is finally very pleased with Reginn's repaired weapon. After using Gram to kill Fáfnir, Sigurð returns to ask Reginn what to do. Reginn instructs him to roast the heart of his brother, and let him eat it. As juice from the dragon's heart foams out, Sigurð tests it with his finger to see if it is done cooking. As the blood touches his tongue, Sigurð understands the speech of birds, who warn him that Reginn intends to kill him. Before he lets any of this happen, Sigurð first wields Gram and cuts off Reginn's head.