What dragon was killed by the hero Sigurd?

What dragon was killed by the hero Sigurd? Sigurd killed the dragon Fafnir.

In the Norse version of the Völsung legend, Fafnir was originally a dwarf or human-like being who became a dragon after taking possession of a cursed hoard. He guarded the treasure on Gnita Heath, where the young hero Sigurd confronted him.

Following the advice of the smith Regin, Fafnir’s brother, Sigurd dug a pit beneath the dragon’s path and struck upward with the sword Gram. The blow pierced Fafnir’s heart. Afterward, Sigurd cooked the dragon’s heart for Regin, accidentally tasting its blood and gaining the ability to understand birds. Their warnings revealed that Regin intended to betray him, so Sigurd killed Regin as well.

Fafnir is sometimes confused with the dragon in the German Nibelungenlied, where the hero is called Siegfried. The stories are closely related, but Fafnir is the distinctive dragon’s name in the Norse tradition. Sigurd is consequently known by the epithet “Fáfnir’s bane.”