I remember being left in a state of gleeful astonishment when I first heard the music of The Pogues. There they were, playing raucous punk music with old acoustic instruments, with tin whistle and accordion, with mandolin and hurdy-gurdy, with banjo and bodhrán. They caught the spirit of punk and made it seem like a natural outgrowth of Celtic drinking songs and folk dances.
The music of Grylle leaves me in a similar state of gleeful wonder, translating the spirit (and some of the sounds) of black metal through ancient instrumentation and the enthralling accents of antique melody. The music and the inspirations may have been born within that most “outsider” of extreme metal genres, but Grylle has then stepped outside of even that, while keeping one foot in the black circle.