Jenks Miller's ambitions with Horseback take an intriguing turn on Half Blood, almost as if his work in other bands like Mount Moriah and elsewhere are starting to feed back into his vision of an American black metal as something always rooted in a deeper Americana to start with.

It could also be due to the expansion of the band into a solid quartet, but throughout there's a feeling of mystic invocation and vocal extremity not so much crossed with a stately form of classic country-rock fusion as it is growing out of it.

Its initial appearance with the opening "Mithras" can be jarring, with a slow, twisted boogie groove being the core more than Miller's now trademark rasp.

By the time of "Arjuna," though, it's almost like Horseback has figured out a perfect single to represent the album, with a core snarling hook and punch, and even a much calmer spoken word moment which has the same impact as a guest verse on a top-flight hip-hop or R&B single, all the while glowering.

This said, the conclusion of the album brings out those even more ambitious realms that Miller has explored in the past, thanks to a three-part effort collectively called "Hallucigenia." The first part hits with drift and flow, the rhythmic growling punctuating a looped, sweeter feeling, something more serenely reflective rather than stern; a wolf at a very secure door.

"Hallucigenia II" brings in darker rumbles and echoes in place of peace, a distorted crumbling howl and a new organ piece leading into end-is-nigh drums and a simple but strong guitar line feeling like a progression to the end, while "Hallucigenia III" goes into full-on evil drone and soft tone combinations, a steady understated pulse to the finish.

Assuming these are all further launching points for Miller's next moves, it all just whets the appetite for what might follow.