Which opera, if any,  Venus and Adonis or Bluebeard's Castle has more acts ?
Venus and Adonis (opera) Venus and Adonis is an opera in three acts and a prologue by the English Baroque composer John Blow, composed in about 1683. It was written for the court of King Charles II at either London or Windsor. It is considered by some to be either a semi-opera or a masque, but "The New Grove" names it as the earliest known English opera.
Ages Ago Ages Ago, sometimes stylised as Ages Ago! or Ages Ago!!, is a musical entertainment with a libretto by W. S. Gilbert and music by Frederic Clay that premiered on 22 November 1869 at the Royal Gallery of Illustration. It marked the beginning of a seven-year collaboration between Gilbert and Clay. The piece was a critical and popular success and was revived many times, including at St. George's Hall, London in 1870 and 1874, and in New York in 1880.