FTP name this Guiseppe Verdi opera featuring the "Anvil Chorus", which translates as "The Troubadour."
It has four acts entitled "The Duel," "The Gypsy," "The Gypsy's Son," and "The Penalty." It is said that the role of Azucena is the most difficult contralto role of all time, calling for no less than twenty trills in the aria "Strida la vampa", while maintaining harmony in her duets with Manrico. FTP name this Guiseppe Verdi opera featuring the "Anvil Chorus", which translates as "The Troubadour."
It has four acts entitled "The Duel," "The Gypsy," "The Gypsy's Son," and "The Penalty.
{Il Trovatore} (prompt on "The Troubadour" if given early)