Answer:
it might be at least more than 20 year
In opera, the libretto is the words or lyrics, as distinct from the music.
The correct answer is Teiresias. He is the character form the play Antigone by Sophocles where his presence is in the climax. It is when Creon finally relents and agrees to do the right thing - bury Polynices and pardon Antigone.
The answer is VALUE hope this help:)