The only unanswerable question about Melechesh's fourth album, Emissaries, is whether its one of 2006's best black metal albums, or best world metal albums.

Yes, conservative world music fans may positively tremble at the thought, but it wouldn't be a stretch to saddle these proponents of "Mesopotamian Metal" with the world metal tag, such is their persistence in incorporating Middle Eastern flavors -- both contemporary and as old as civilization itself -- into their furious metallic onslaught.

Steeped in Chaldean mythology from top to bottom, Emissaries is a collection of Sumerian spells and Mesopotamian mysticism supported by a blistering barrage of extreme metal ferocity that's really rather fitting when you consider the bloody brutality of the stories being told.

Take "Rebirth of the Nemesis," for instance, whose lyrics rewrite the Babylonian creation epic of Enûma Elish (by resurrecting the mother goddess Tiamat to exact revenge upon her murderer and supreme successor Marduk) to the sound of vicious but cleanly recorded black metal infused with Middle Eastern melodies and beats emphasizing the 3 and 4.

The fact that vocalist Melechesh Ashmedi's strangled rasp might sound like a Mesopotamian Muppet to some could undermine the ambition of such fascinating subject matter, but when the song reaches its cathartic conclusion by way of melodic chants of "Lla Tchaf Lla -- Tiamat -- Enuma Elish is re-written," listeners who get it will most certainly feel like head-banging and belly-dancing at the same time! With the exception of the all-acoustic, no metal instrumental "The Scribes of Kur," which is performed entirely on traditional instruments, repeat collisions of these stylistic extremes prevail throughout the remainder of Emissaries, with special kudos going to standout alchemies like "Deluge of Delusional Dreams," "Gyroscope" (boasting a more moderate pacing), and the epic "Sand Grain Universe," with its dramatic speed shifts and punctuating guitar harmonics.

In short, Emissaries is a consistently mesmerizing voyage into rarely explored music realms (for a similar experience with less black metal, see Orphaned Land) and, even longtime Melechesh fans are likely to agree, constitutes a new high-water mark for the group.