Which opera has more acts, Riders to the Sea or Lucio Silla?
Lucio Silla Lucio Silla (pronounced , ] ), K. 135, is an Italian opera in three acts composed by Wolfgang Amadeus Mozart. The libretto was written by Giovanni de Gamerra.
Sant'Alessio Il Sant'Alessio ("Saint Alexius") is an opera in three acts composed by Stefano Landi in 1631 with a libretto by Giulio Rospigliosi.