"Massive" is but one way to describe Aion Sitra Ahra - the other, "ghostly." For however requisitely crushing ADVERSVM's funeral doom is, there's equally a sense of ethereal drifting, that shadows forever lurk between the tectonic shifts known as riffs. And it's generally more blackened than most extreme doom, for the original idea behind ADVERSVM was to create art more sinister than black metal and death metal, and to manifest this sound with apocalyptic verses.
Indeed, MORBID DARKNESS is what you'll find with Aion Sitra Ahra: no repose, no remorse, no mercy. Simply, it sucks the life out of you...as ADVERSVM want it to be. But this is just the beginning, as the band already have a second album in progress. Hail emptiness and inertia.