Mastodon’s third album is a vicious slab of metal that intends to crush all that cower. To get an idea of what “Blood Mountain” is all about, imagine what it would have sounded like if cavemen had invented guitars and drums instead of the wheel. It’s that aggressive.

The frenzied opening track “The Wolf Is Loose” is the audio equivalent of the Running of the Bulls; drummer Brann Dailor’s relentless fills pound the listener into submission well before the vocals enter. Dailor sounds like Buddy Rich in a metal band; he can shift time signatures with ease and breezes through the metal shuffle of “Crystal Skull” and the off-kilter rhythms of “Capillarian Crest.”

Aside from the shredfest “Capillarian Crest,” guitarists Bill Kelliher and Brent Hinds take on more of a supporting role for much of the album’s first half. When they do heat up on “Bladecatcher” and “Colony Of Birchmen,” both guitarists flex knotty, angular solos and exotic harmonies.

The duo are more about playing chaotically than melodically, which suggests both have spent time listening to Slayer.

Production-wise, “Blood Mountain” is solid. The album could benefit from tighter and more flowing song structures, but the riffs and the melodies are there.

Heavy, lethal, but unrefined; Mastodon is living up to its name.

Keith Beebe is a music critic for the

Northern Star.