Birth (1984)

Aqualoid was a prosperous planet, but an attack from a mysterious life force, the Inorganics, transforms it into a post-apocalyptic shell of its former self. When Nam finds a mysterious sword, he is suddenly the object of a planet-wide chase. With the Inorganics closing in, will Nam and his friends discover the secret of the sword and save their world? Or will they destroy Aqualoid in favor of a new Birth? (Source: AniDB)