I haven't heard "Under the Sign..." or "Destroyer", I admit, but I can't imagine that any of these releases would be better and more interesting than this one. "Incipit Satan" is full of experiments, which makes this album so unusual and interesting. Every song here brings something new, but it’s not a matter of different riffs - it brings something new to Gorgoroth and even to black metal. I don't know any other release of this kind, I would love to know...
"Incipit Satan" has its own sound, based on heavy, fuzzy guitars, that play sometimes simple, but sometimes complicated riffs, melodies or just make noise. Bass is rather hard to hear, so I can't say what is it like. Drums play either extremally fast or slowly. Vocals range from great, wild growls to clean, spoken or sung quotes (I can't name it, actually) and they make a very strong point of the album.
"Incipit Satan" - variety of songs. We have more typical "Incipit Satan" or "A World to Win" here, though both of them have electronical moments in them. We can also hear here few concept songs, like maybe simple but very effective "Litani til Satan", great and different "An Excerpt of X" or "When Love Rages Wild in my Heart" - a song that is definitively not a black metal one. We can find here also an industrial\electro\whatever track - "Will to Power".
The whole album is spectacular at least for me, and though I hadn't heard it for a long time, when I returned to it I was amazed by it. Generally - "Incipit Satan" is for everybody that likes black metal that evolves and turns to something new - something fresh. I would even say that if black metal cannot go the path Emperor or Naglfar, my favourites, have gone, it should go this way.