 There has been a suggestion that this is a corruption of the lore surrounding creatures from Norse mythology, namely the Miðgarð Serpent and Fenriswolf, with some elements of Fáfnir, the gold-hoarding dragon of from the Völsung Cycle.Similarity to the overgrown dragon in "Ragnars saga Loðbrókar" has also been noted; that dragon also grew large along with its gold.The legend that keeping a "brekkusnegill" (black slug) together with gold will make both grow enormous is associated with other bodies of water, namely Skorradalsvatn (see below), Kleifarvatn, and the Hvítá and Skaftá Rivers.