What is the main extended metaphor in Antigone play?

In Antigone, the main extended metaphor is the light/dark imagery. Light imagery is associated with life, hope, and truth, while darkness imagery is associated with death, despair, and secrecy. This metaphor is particularly evident in the play's final scene, where Antigone walks into the tomb and is swallowed by darkness, representing her death and the tragic end of her story.