The transitions lead to the main riff. The tempo is doubled to 188 beats per minute, and the riff is invigorated with an opening gallop (i.e. two sixteenth notes followed by eight note rhythm) on the low E. To the familiar ascending/descending melodic pattern is added the note A, which creates half-step tension with Bb. The first measure is repeated twice, and the riff ends with a chromatic descent from G to F.
