Inquisition play a diverse brand of thrash/death/black metal that digs up many influences but consistently sounds fresh.  The music is incredible.  A head banging feast of balls out Armageddon blast beats, ”Unholy Magic Attack”, and melodic, sometimes a bit folk-ish song structures, “The Initiation”.   “Summoned by the Ancient Wizard” is fantastically heavy, the use of time changes only enhances this.  The one instrumental here, the title track “Into the Infernal Regions of the Ancient Cult”, is a frantic exercise in speed that seemingly melts into a slow dirge pace.  There are lots of twists and turns with a few spoken word recordings (non-Dagon voiced) thrown in for a wicked effect.  “Solitary Death in Nocturnal Woodland” is a long one, 9 minutes of ominous, chilling sounds.  More of a doom inspired song it stays the pace and features melodic guitar work that conveys a melancholic aura.  The ending track, “Hail the Cult” is another longer song, a bit odd as there is about 4 minutes of music (guitar only) and then 4 minutes of silence before a short pre-recorded bit at the end.  The guitars are so intricate and heavy they lend an epic sound to the track again crossing into folk tinged metal territory.

To single out one aspect is difficult; thunderous drumming to slow doom-like heartbeat is impressive, the guitar work is melodic but also fiercely rhythmic and wonderfully riffy. 
The vocals is where there may give reason to pause.  These are not your typically screeching black metal or punkish thrash metal vocals. Not by a long shot.  Inquisition and Dagon in particular, went a route that will either be embraced or pushed away.  The vocals are a mix of raspy, deep baritone almost spoken word cadence.  The only thing to even (very remotely) compare it to would be Attila Csihar performance on De Mysteriis Dom Sathanas.  That being said after listening to the complete cd it’s hard to imagine any other type of vocal style working so well!  They simply are the proverbial icing on the cake (a bloody, malevolent cake it would be) adding that last sinister touch to a work that is already disturbing dark and creepy.