Andvari, meaning “careful one” in Old Norse, is a dwarf who lives underneath a waterfall and has the power to change himself into a fish at will. Andvari had a treasure of gold and a magical ring named Andvaranaut. It is said, his magic ring helped him become wealthy. The Völsunga saga tells us: Loki used a net provided by the Norse goddess Rán, to catch Andvari while he was shape-shifted as a pike. Loki then forced Andvari to give up his gold and his magic ring, Andvaranaut. Furious at Loki and at losing his precious, Andvari cursed the stolen gold and magical ring which would destroy anyone who possessed it. One day, the Æsir gods Odin, Loki, and Hœnir, were traveling and came across Ótr (otter), who was shape-shifted as an otter. Ótr was the son of Hreidmar, King of the Dwarves. Loki killed the otter (which was Ótr shape-shifted as an otter) with a stone and the three Æsir, Odin, Loki, and Hœnir, skinned the otter.

Later that day, the gods came to King Hreidmar’s dwelling and showed off the otter’s skin. Hreidmar, King of the Dwarves recognized the otter skin as being the hide of his son Ótr and demanded justice

King Hreidmar and his remaining two sons, Fafnir and Regin, seized the gods and held them captive while Loki was sent to gather a ransom (weregild).  Loki was to have the otter skin of Ótr stuffed with gold and have the outside of it covered with red gold. This was the weregild demand as reparations for slaying Ótr.

Loki fulfilled the task by gathering the cursed gold of Andvari as well as the magical ring, Andvaranaut. Loki knew because of Andvari’s curse that the items would bring about the death and destruction of whoever possessed them.

The curse causes Fáfnir to kill his father Hreidmar and take all the ring and 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 (wyrm, serpent) to guard his treasure. Fafnir denied his brother Regin his share.

Regin seeks the aid of Sigurd who agrees to kill Fafnir to avenge him and his father Hreidmar.

Sigurd kills Fafnir and drinks some of Fafnir’s blood, gaining the ability to understand birds. The birds advise Sigurd to kill Regin because he’d been corrupted by the ring and was plotting Sigurd’s death. Sigurd beheads Regin and keeps the ring and treasure for himself.

Sigurd then meets the shieldmaiden Brynhildr, who pledges herself to him but also prophesies his doom and marriage to another. The ring’s curse affects Gudrun. a beautiful but evil woman rumored to be a sorceress. Sigurd gave the magical ring of Andvaranaut and gave it to Gudrun as his morning gift to marry her daughter.

Corrupted by the Andvari’s cursed ring (Andvaranaut), Gudrun plots against Sigurd and Brynhildr to get the gold for herself and her family. Tragedy follows and after the deaths of Brynhild and Sigurd, Grimhild’s brother Gunnar acquires Andvari’s gold and hides it in a cave.

Years later, Andvari discovers the cave and finds his hidden lost gold. However, his ring, Andvaranaut was lost forever. Legend claims he spent the remainder of his days in search of his lost ring, his Andvaranaut.