Drop D Tuning was brought to the forefront by bands like Sepultura, whose supernaturally heavy sound and machine gun attack on the ear's audible threshold resurrected thrash metal. The Arizona band Kyuss took the musical style a step further with monster guitar riffs that weighed in heavier than a school bus full of fat children.
Two highly recommended bands that continue innovating within the murky depths of Drop D are Helmet and Korn.