First released on Utech Records in 2009 then picked up for wider distribution by Relapse the following year, The Invisible Mountain features Horseback -- and specifically its main force, Jenks Miller -- exploring that which is metal, in a post-stoner/psych/black/whatever-you-want vein.

It isn't pure anything, which is one of its best advantages -- as has been the case with so much 21st century metal, Horseback aims to rework and recombine the past as it wishes rather than pledging a specific adherence to anything.

So if the rasped, half-hidden vocals apparent from the start on "Invokation" are definitely partially descended from Scandinavian forebears, the doom-laden, slow-rolling arrangement, part feedback crunch and part piano, feels more like a bad trip from somewhere between the original acid rock headnodders and later reworkers of the approach like Monster Magnet and Sleep.

It's a simple but effective combination that sets the tone of the full album, four tracks in all that feel like part of a larger piece but are presented as individual songs rather than simply being something bigger split up into something else.

The serenity that the brilliantly named "Tyrant Symmetry" creates is nicely contrasted with the shift into the title track, no less steadily entrancing but with more guitar overall and a sense of suddenly present power that had been held back beforehand, beautiful but threatening.

The aptly named "Hatecloud Dissolving into Nothing" ends the album on a different note, soft guitar notes and drones building into a gentle drumless arrangement, with hollow, distant vocal parts suggesting a present but dying malevolence.