Die Nibelungen (1924) filmed at UFA (Read the book "The UFA Story"). Director Fritz Lang, the original story "Siegfried's Tod" I have seen it with German subtitles and other versions with English subtitles. Paul Richter (Siegfried) was in 45 other films, from 1921 to 1972.
Siegfried (Paul Richter) is the son of the King of Xnnetn (Sigmund). He forges his own sward so sharp that it cuts chicken feathers. He is told that near the Rhine at Worms the King of Burgundy (Gunter) and his sister, Kriemhild is at a castle. Siegfried, "On the hour I leave for Worms to win Kriemhild"..."Show me the way if you want to live!" He falls for the "I know a short-cut" routine. Die Nibelungen snickers when he is out of earshot; "Your way leads not to Worms, but to Death" Guess who lives in the heart of the forest? Yep it is Fafnir the Dragon. Poor Fafnir was minding his own business getting a drink when Siegfried gets that "What can I hack" look on his face. The dragon even wags his tail with the approach of Siegfried. I won't give you the blow by blow. I'll just say that smoking can kill you. Fafnir gets stuck for the drinks and dragon blood drinks allows you to understand the birds. A little birdie tells him that bathing in dragon blood will make him invulnerable. You guest it cover your eyes. Oops look real quick. "Dragon tail flicks linden leaf on Siggie's back." Can you say Achilles heel? Meanwhile back at the castle Volker von Alzey is already singing to Kriemhild of Siegfried' triumph over Fafnir. From here it goes on to deal with treasure, invisibility, and all the stuff that Teutonic mythology holds.