“Enter Sandman” from the Black Album contains a more famous, and slightly more complicated, example of thematic evolution as the examples from “The Thing That Should Not Be.” The song begins with one of the most recognizable riffs in the metal genre. In a clean-tone guitar, the melody begins from the low E and ascends up an octave and continues to G before descending to Bb and down again to A, and followed by an ascent up to E. The rhythm is distinguished by quarter note values tied over the bar lines and the quarter note A on the third beat of the first full measure.
