Twenty years since its inception, "black metal" has become as useless a term as its original parent "heavy metal" when it comes to properly describing its many offshoots and subgenres.

After all, how can a single label possibly encompass both the primitive rawness of a Darkthrone and the classical music-derived grandeur of a Dimmu Borgir -- not to mention the innumerable strains of Viking, post-thrash, and death-bordering varieties out there? Norway's Borknagar are one of the longest-tenured members of the incomparably bustling Scandinavian black metal scene, and they too have clearly outgrown simplistic genre definitions over the course of ten years and six albums.

2004's Epic is that sixth album, and, true to its title, it finds the band led by guitarist Oystein G.

Brun crafting yet another ambitious collage of metal styles into what they like to call "majestic black metal." Not quite as symphonic in scope as the likes of Emperor or the aforementioned Dimmu, nor as obsessed with the Viking and folk elements like Enslaved or Windir, the compositions of Borknagar are based on more traditional rock songwriting structures; and they attain their greatest distinction through ample and eclectic keyboard colorings, and a literal laundry list of different vocal techniques enriching their creative palette.

The recent addition of accomplished vocalist Vintersorg is crucial to this last mission, and he once again proves himself equally comfortable with black metal's requisite strangled shrieking as with outright melodic singing.

In fact, Epic proves that he's easily one of his generation's best singers working within the extreme metal idiom.

Throw in the expert musicianship and inventive arrangements fashioned by the rest of the group and resulting album highlights such as "Future Reminiscence," "Sealed Chambers of Electricity," and "Resonance" positively sparkle with memorable riffs, tasty keyboards, and, most importantly, furiously head-banging passages.

The psychedelic guitar chimes of "Traveller" and the dramatic quasi-power ballads "Circled" and "The Wonder" (only the cookie monster grunts don't comply, but they work anyway) show Borknagar's willingness to defy metal's boundaries, while the remarkable instrumental, "Weight of the Wind," simply breaks with all preconceptions by combining beautiful piano, mesmerizing keyboards, and spidery guitar leads in equal measures.

All in all, Epic is a particularly satisfying, distinctive, and at times even surprising release from these "black metal" veterans.