The cycle is a work of extraordinary scale. Perhaps the most outstanding facet of the monumental work is its sheer length: a full performance of the cycle takes place over four nights at the opera, with a total playing time of about 15 hours, depending on the conductor's pacing. The first and shortest work, Das Rheingold, typically lasts two and a half hours, while the final and longest, Götterdämmerung, takes up to five hours, excluding intervals. The cycle is modelled after ancient Greek dramas that were presented as three tragedies and one satyr play. The Ring proper begins with Die Walküre and ends with Götterdämmerung, with Rheingold as a prelude. Wagner called Das Rheingold a Vorabend or "Preliminary Evening", and Die Walküre, Siegfried and Götterdämmerung were subtitled First Day, Second Day and Third Day, respectively, of the trilogy proper. The scale and scope of the story is epic. It follows the struggles of gods, heroes, and several mythical creatures over the eponymous magic ring that grants domination over the entire world. The drama and intrigue continue through three generations of protagonists, until the final cataclysm at the end of Götterdämmerung.