Read manga: Youhen Nibelungen No Yubiwa

manga
Summary:

The story is set in a world were gods control the heavens, giants the earth, and nibelung (a strange looking race) the underground.The main character (Sigurd) wanting to learn what fear is makes his entrance during a battle between the (almost extinct) humans and giants. Things weren't looking good until he pulls out a broken sword that scares even the giants. At the same time, a goddess descends along with a meteor shower.What is the importance of the broken sword who can only be fixed by "the fool without fear"? What's the mission of the goddess on earth?