From http://woundsoftheearth.blogspot.fr

Basics:
From the moment I got word of this split, I was excited. Flint Glass is one of my favorite projects and I love his blend of dark sci-fi atmospherics and industrial/idm/techno. Nyarlathotep is still one of my favorite records (you can't go wrong with HP Lovecraft references/influence). And to see him working with crushing space ambient producer Collapsar was quite exciting. Additionally, this was released in various formats: it was released as a limited edition vinyl via SEALT, on CD by Ant Zen, and digitally by Flint Glass's own Brume. The vinyl contains the two long-form tracks "The Servants of Wrath part I" and "...part II", while the CD and digital versions contain 5 additional remixes. I also want to mention that the artwork is absolutely stellar and fits this album perfectly!

Stuff:
As predicted, the two original tracks are nothing less than spectacular. Each one is over 20 minutes long, coming in at 21 and 26 minutes respectively. They are both highly dynamic and show these artists pushing what can be done within the "ambient" genre.

The Servants of Wrath part I:
This one, overall, is a bit more on the ambient side of things. It opens with clean cosmic droning which immediately transport you through the endless voids of space onto an ancient planet littered with dead technology. While it has some similarities to the Collapsar solo record, overall it is much cleaner which allows it to feel exceptional spacious and dynamic. These textures are truly colossal and worth of the grandeur that Lovecraft writes of. After about 5 minutes they bring in some of the trademark Flint Glass sounds and it slowly builds with slow, plodding percussion, giving it a very cinematic feel - think of spaceship scene in a modern take on Alien. One of the best parts of this album is the incredibly deep and dynamic atmospheres which continually shift and mutate between the percussive sequences, and they are in full effect throughout this song. After the section of slow, heavy drum hits, everything collapses into a pit of subtle darkness before slowly building back up. From 11 or 12 minutes on, it feels similar to a typical Flint Glass track. There are many trademark noises and the click-y IDM-influenced percussion dominates. From here the track shuffles between minimal ambient sections embodying the vast emptiness of space, and similar beat-driven parts, conjuring visions of strange space stations and foreign planet surfaces, several more times before coming to a close.

The Servants of Wrath part II:
The second track contains the same general characteristics and sounds, although it brings in percussion much sooner. Quickly we're thrown into a very Flint Glass-esque track - again with the click percussion toiling underneath impressively sci-fi atmospheres. There are some spoken word samples and crunchy (though subdued) noise in the background which must be the Collapsar influence. Nothing short of cinematic masterwork. Part II exhibits a similar flow to Part I, although the parts with drums are a bit heavier and more driving. Some of the harshness of Collapsar's work shines through and enhances the Flint Glass palette.

In addition to the 2 album tracks, there are also 5 remixes. As is the case with most remixes, the bulk of these are, sadly, disposable. The only remixes worth mentioning are the ones from Hologram_ and Iszoloscope. Hologram_ provides a captivating industrial-y IDM flavored mix with clicky, complex beats dancing beneath a charming melody and exceptionally futuristic atmospheres. Iszoloscope turns his track into a heavy, rhythmic noise/dark techno banger. He does an exceptional job at allowing his crunchy & driving percussion to coexist in perfect harmony with the massive atmosphereics of the original work. A superb example of how to make interesting, deep, and well produced rhythmic noise. These are both great tracks which expertly utilized some of the best elements of the originals while enhancing them with their own sounds & flavor, and I can see myself listening to frequently.

Overall:
An exceptional split that sounds like the two artists fully merged their brains and composed as one. Everything fits together nicely and nothing feels strange or out of place. I feel that the strengths of both artists shine through. The excellent mixing and production further enhance the pieces and turn them into celestial masterpieces. Definitely a must hear for fans of either artists or space-themed ambient/industrial in general.
http://woundsoftheearth.blogspot.fr/2015/06/flint-glass-collapsar-deus-irae.html

They have discovered something, our intrepid duo. A place where the world has ended, where humanity walk on a razor edge between existence and extinction; where the conceits of orthodoxy have become the ultimate expression of power. The remnants of civilization cannot explain anything, no control remains; vestiges of the previous age which mankind thoroughly put an end to only serve now to prey upon the few left who cannot understand what has happened. In this place, two opposing camps have arisen to deliver their own version of what the truth now is. The leading faction is who this album provides a soundtrack for and they are a loving bunch... The Servants of Wrath.

This lot deify the one who began what would lay waste to the planet, a man to focus their own love of nihilism through. There's just one problem, no one knows what he looks like or where he resides. A quest is therefore undertaken to find the object of their worship in order to capture an image of him, the goal being to prove his existence to any who disbelieve. All throughout the journey the vast scope of destruction which this god of theirs has wrought comes into plain, painful view. The annihilation has been thorough although there are some notable escapees. The diabolical artificial intelligence of the Big C eclipses everything else our pilgrims encounter as its now been reduced to consuming human beings in order to survive.

It is a land where life has little, if any, value. Armed with their formidable arsenal of equipment, Flint Glass and Collapsar depict the lonliness and barbaric hostility of the search for Lufteufel. This is the sort of post apocalyptic setting which only the continual threat of nuclear war could provide. In the late 1970s there wasn't a whole lot of belief in the future, a kind of perpetual malaise had set in. On one side there was the East and on the other the West. Two opponents with an intractable doctrine of mutual mistrust and cold contempt. I remember the early 1980s where this book is set with even sharper clarity. 1982 would have been the perfect choice for the end, no one would have been surprised; those in charge certainly wanted it.

It is dark and terrifying what these gentlemen have composed, two long form pieces which go through several movements as though they are meant to coincide with actual chapters in the book. If a film ever is made of this, what I'm hearing here had better be what gets used for the score. Horrible though the outcome may be we have no one to blame but ourselves. The nature of faith and the foundations of belief were what Dick and Zelazny mainly addressed with "Deus Irae" and I have to commend those who composed this music for somehow staying true to that spirit. They don't back down or give an inch! This is an epic symphony of droning decay, a litany for the ruins and a searing indictment of technology.

Man and his need to believe will be the undoing of us all.