At the risk of inviting a landslide of the I-can’t-believe-you-forgot-abouts, New Zealand is not a country readily associated with black metal. Still, quality over quantity, eh? In War of All Against All Diocletian have released a poisonous little gem of misanthropy that stands as one of the more enjoyable vomitings of unreconstructed death-black wrath I’ve heard this year. (‘War metal’ if you are a trainspotter of microscopic subgenres). One member, guitarist and vocalist Phil Kusabs,lists on his CV not just Ulcerate but Canadian underground heroes Blasphemy. Whilst the former are a remarkable act, it’s unshakeably the latter whose influence seeps through most clearly here, along with those other ancestral pioneers who envisioned black metal as unrestrainedly bellowing occult noise rather than frostbitten museum piece.

As befits its epically Hobbesian title, War of All Against All channels substantial malign grandeur, through its rumbling, growling sound and its often slow, militaristic riffing. Opener Black Dominion starts life as a primordial soup of crawling doom horrors, before leaping into action as a livid, tangled mesh of clattering drums and deep and fuzzy guitar riffs that sounds like howls of infernal anger. The vocals are faded out as a distant hiss, making for a harsh and murky sound that evokes the baleful energy of bands like Sarcofago or Blasphemy.

Diocletian are at their most distinctive in their slower moments, in which their crowd-pleasing extreme metal noise becomes spine-tinglingly imposing. The last word in this respect is the 16-minute closer, Fortress of the Unconquerable, a glowering marathon of crackling feedback and leaden-footed blackened-doom grand-guignol. Still, the best tracks are where these sides are allowed to fuse, as with All Against All, where cumbersome slow shapes seem constructed out of riotous blasting; an effect comparable to the pestilential likes of Teitanblood.

This, then, is an eminently respectable extreme metal album. It isn’t something especially original, but the depth and weight of the sound, and the down-tempo grimness of many of the riffs, gives it a heavyweight feel that renders it worthy.