Fafnir

In Norse mythology, Fáfnir (Old Norse and Icelandic) or Frænir is a son of the dwarf king Hreidmar and brother of Regin, Lyngheiðr, Lofnheiðr and Ótr. After being affected by the curse of Andvari's ring and gold, Fafnir became a dragon and was slain by Sigurd.

In the Icelandic Volsunga Saga (late 13th century), Fáfnir is a dwarf with a powerful arm and fearless soul. He guards his father's house of glittering gold and flashing gems. He is the strongest and most aggressive of the three brothers.

Regin recounts to Sigurd how Odin, Loki and Hœnir were traveling when they came across Ótr, who had the likeness of an otter during the day. Loki killed the otter with a stone and the three Æsir skinned their catch. The gods came to Hreidmar’s dwelling that evening and were pleased to show off the otter's skin. Hreidmar and his remaining two sons then seized the gods and held them captive while Loki was made to gather the ransom, which was to stuff the otter’s skin with gold and cover its outside with red gold. Loki fulfilled the task by gathering the cursed gold of Andvari as well as the ring, Andvaranaut, both of which were told to Loki as items that would bring about the death of whoever possessed them. Fáfnir then killed Hreidmar to get all the gold for himself. He became very ill-natured and greedy, so he went out into the wilderness to keep his fortune, eventually turning into a serpent or dragon (symbol of greed) to guard his treasure. Fáfnir also breathed poison into the land around him so no one would go near him and his treasure, wreaking terror in the hearts of the people.

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