Which opera has more parts including acts and tableaux, Le roi d'Ys or Stiffelio?
Stiffelio Stiffelio is an opera in three acts by Giuseppe Verdi, from an Italian libretto by Francesco Maria Piave. The origin of this was the novel “Le pasteur d’hommes”, by Émile Souvestre, which was published in 1838. This was adapted into the French play "Le pasteur, ou L'évangile et le foyer" by Émile Souvestre and Eugène Bourgeois. That was in turn translated into Italian by Gaetano Vestri as "Stifellius"; this formed the basis of Piave's libretto.
Le Diable amoureux (ballet) Le Diable amoureux (also known as Satanella or Love and Hell) is a "ballet pantomime" in three acts and eight scenes, originally choreographed by Joseph Mazilier to the music of Napoléon Henri Reber and François Benoist. The libretto by Jules-Henri Vernoy de Saint-Georges is based on Jacques Cazotte's 1772 occult romance "The Devil in Love". The work was first presented by the Ballet du Théâtre de l'Académie Royale de Musique in Paris on 23 September 1840, with Pauline Leroux (as Uriel), Mazilier (as Alvaro, for ballet his name is Frederic), and Louise Fitz-James (as Lilia).