Loosely labelled a death metal band, Opeth is really so much more, with their mix of mid-paced riffing, acoustic guitar interludes, and frequent tempo and mood changes continuing to push the boundaries of extreme music. Opeth write long songs (often over ten minutes long), but the diversity of the songwriting keeps things interesting. The phrase "progressive death metal" has been used before, but it probably fits Opeth better than any other single band. While the earlier albums are undeniably more brutal in their approach (and often regarded as fan favorites) it's the later releases, starting with 2001's Blackwater Park, where all the pieces truly fit together. An outstanding band.