Another Warhammer 40000 book. Not as good as Gaunt's Ghosts, but I've been following it. . . talking about each work will doubtlessly contain spoilers for the previous. The Blood Angels of the title are a chapter of Space Marines, among the originals (the First Founding).
Deus Encarmine and Deus Sanguinius are a duology, not two novels, better in an omnibus than standalone, despite still having a somewhat awkward and unsatisfactory ending for Deus Encarmine and some awkward infodumping in Deus Sanguinius for people who hadn't picked up the first.
It opens with Brother Rafen and his squad, under his mentor Brother-Sergeant Koris, coming into contact with the Chaos-tainted Space Marines Word Bearers. The use of sorcery is driving them back when an force of new Blood Angels -- including Rafen's brother by blood, Arkio -- turn the tide. Then even more vicious sorcery brings them to their knees, and only Arkio's bold plan saves them. As a reward, he is allowed to present the Spear of Telesto, an ancient artifact that the Blood Angels have just recovered, in the chapel, and holding it has him take on the aspect of their primarch Sanguinius.
The Inquisitor Stele, instrumental in the recovery, shows that he is Up To Something.
This was Swallow's first book, and I think it shows since he doesn't plumb the dramatic irony of seeing what Rafen has to stumble through. (The writing's also frequently clumsy.) On the other hand, as the Blood Angels are drawn into believing Arkio the Reborn Angel, and Rafen struggling with whether it's true or whether he's just envying his younger brother. Sorcery, treachery, battle, and drama in abundance. I also particularly like the way it handles chances and coincidences and making them make sense, and a convincing and literal vision.
Red Fury takes up with Rafen, now Brother-Sergeant, leads his squad on a planet where Chaos forces have taken hold. The Flesh-Tearer Space Marines drop a building on their heads. They know the Blood Angels will survive, and just want to be annoying, partly because they think they have come to interfere. In fact, Rafen came to deliver a message, to ask their Chapter Master Seth to come to a conclave of chapters -- successor chapters, also derived from Sanguinius.
Seth comes. So do many other chapters that derive from Sanguinius. And the Blood Angels Chapter Master, Dante, reveals to them what happened and that the Blood Angels are badly depleted. At this level, usually what happens is that the chapter is broken up, and its Marines allocated to other chapters. However, being the First Founding chapter, what the Blood Angels ask for is a tithe of men from their successor chapter, to replenish their numbers. The Chapter Masters are not pleased with this request, with Seth leading the objections.
Meanwhile an Apothecary of the Blood Angels is trying to replace the fallen members with his own experiments. He receives aid from a mysterious figure from the Adeptus Mechanicus -- his servant sees how dangerous this figure could be, but the Apothecary is blinded by his need. When he attempts to show it to the Chapter Masters, it goes awry. Badly. And then things go from bad to worse. Rafen is one of those sent to stop the experiments, and they find that the figure is, in reality the infamous Fabius Bile. Ancient and treacherous sorcerer and mad scientist.
And then there is real danger that the results will overwhelm them all.
At the very end of Red Fury, Rafen is told that Bile stole some of the blood of the Primarch and that he is to track him down and punish this blasphemy, and retrieve the blood. Black Tide starts with his squad on a tau (alien) colony and the discovery that Bile is gone and knew they would follow them. And this was their last lead.
Rafen is Not Pleased.
But Seth sends word to the Blood Angels that the Flesh-Tearers have a lead, and want to be part of avenging the insult. Dante agrees and sends word to Rafen to cooperate. They join forces with a Flesh-Tearer squad, led by Noxx (featured in the last book, too), and together they track down an Adept of the Adeptus Mechanicus, take over his ship, and force him to bring them to the planet where he dealt with Fabius Bile. They discover it's infested with tyranids -- which is to say, horrific all-devouring hordes of alien monsters. Bile has his lab in the middle of this.
By sacrificing a space ship, they manage to launch a submarine into a sea infested with tyranid kraken, and set out to attack a heavily defended post. Adventure, danger, death ensue.
As I was reading this one, I was thinking this is a tie-in, and Fabius Bile is a character in the game. There is no way that Rafen's going to be allowed to thwack him over the head and put an end to him. So -- how can this book resolve? And I will say that he managed to pull off an ending despite that.