Four out of the five Birds of Prey have impeccable (impeckable?) credentials as a stonerish sludge band. The vocalist is Ben Hogg of Beaten Back to Pure, and it also features Erik Larsen, member of many bands including The Mighty Nimbus and Alabama Thunderpussy. The fifth member, the drummer, Dave Witte, is in Municipal Waste, Discordance Axis and Burnt by the Sun. If that leads to expect a hard grooving sludge act with interspersed thrasy grind influences, then you are quite right.

It is unsurprising, then, that this combines steamy rock thunder with a crunching sound to break your thumbs, as on Tempt the Disciples. But this familiar routine is entirely transformed by thrashing energy, as with the galloping Taking on our Winter Blood, as well as shuddering death spasms such as those that grip opener Mama. In fact, there are times when you feel it could do with bringing back a few catchier grooves, so enthusiastically do death and thrash make their presence felt.

Hogg’s vocals are abrasive bellows, more so than in his performances with Beaten Back to Pure, and this further tips the balance here away from Southern rock sleaze towards extreme metal menace. At times he almost has an L. G. Petrov quality, and gradually you start to notice a distinct wider resemblance to Entombed’s Wolverine Blues, albeit with a meatier sound. Embellishments here are fairly rare. Guitar solos are generally kept to a minimum, and often when they are there, they squeal away in the background, giving a riff dynamic effect without stealing its thunder. A notable exception is the dazzling protracted roar that fills Blind Faith with malevolent energy in the finest metal tradition. Another high point is closer Giving up the Ghost. It’s a riotous death-thrash rattle, again reminding me of Entombed, but this time something more recent, such as Serpent Saints.

Listening to this, I keep expecting every buildup to explode into a titanic blues riff that drills its way into your head and refuses to leave, but this never quite happens. It’s a brutally enjoyable punchup between sludgey groove and extreme metal, with crushing blows being dealt by either side, but with nobody quite ending up with permanent injuries.