Das Rheingold
Each character in the opera has his own musical leitmotif which can change and combine to show their changing moods and situations. There are big, heavy chords for the giants, creepy chromatic winding music for Loge, the god of fire, who is supposed to be very crafty, dignified music for the Earth Goddess Erda etc. There is a special leitmotif for the curse, which is heard at various times in all four operas.