All in all, a good series, but why only a single squad of Space marines would accompany a Mechanicus ship the size of what sounds like Russia, China, and Europe, didn't really make sense. Maybe a company or half-company would have been more appropriate.
But I digress, as this story isn't really about the Space Marines (even though one is a main supporting character), but rather it is about the near-insanity, arrogance, audacity, and their greedy oppression of knowledge by deeming themselves worthy of determining who gets access to that knowledge. Basically the Mechanicus in the story (save a rare few) are pompous @$$holes. This is nothing new.
The third book culminates the story of Archmagos Kotov, a near-deposed Archmagos who has suffered great amounts of misfortune, but who still gets the green light to travel beyond the known Imperium, beyond known space, to find a lost Archmagos by the name of Telok. Insanity and mayhem ensue as we discover the lost magos has created something akin to Warworld from DC comics, and has mastered technologies that the Mechanicus hasn't yet rediscovered. Aboard the Speranza (A name that is acknowledged in the books to refer to 'Hope' in an ancient Terran language), accompanied by five Black Templars, an armored Cadian battalion, and a whole continent-sized ship full of Mechanicus extras, we sail off passed the Halo Scar.....
*****************SPOILERS SPOILERS SPOILERS (KINDA)******************************************* ********************************************
Guardsman Hawke from the Iron Warriors Omnibus fame returns, although the way he is written has a feeling of Star Wars: New Hope, where there's a Cptn Antilles commanding the Tantive V corvette, who has nothing to do with Wedge Antilles of Rogue Squadron. He does have zero trust for the Mechanicum, but there's no recap as to why, so you need to read the IW Omnibus.
There is some Necron tech, some quite spectacular device called 'The Breath of the Gods', which shapes entire solar systems by pulling energy from the past and future...... really, it's very timey whimey, wibbly whobbly. However, psychotic Archmagos Telok does pretty much confirms that the Neconr Dragon (I forgot the name) sleeps beneath the sand of Mars. If they do an End Times for 40K like they are for Fantasy, this would be a very interesting story line... Does the Mechanicus praise the Necron God as the Omnissiah when it wakes up??
Some callouts, as it becomes apparent through the read that Graham McNeil is a fan of Star Wars
Page 259, midway down: "He lifted his hands, like a....telekine striving to lift a starship". I read this as a reference to Luke Skywalker trying to lift his X-Wing out of the swamps of Dagobah.
Page 264, a few lines up from the bottom, two techpriests are in gunnery chairs, and one blasts an enemy and let's out a gleeful shout. The other scolds him by saying "Don't get cocky..." The scene is almost completely setup as that in Star Wars: New Hope when Tie Fighters are chasing the Falcon, and Hand and Luke man the guns.
Page 337: there is a single, quick reference to the Kaban Machine from the Horus Heresy series.
Page 382, a few lines from the bottom: Archmagos Kotov says "How far we have fallen, but how far we may yet climb" To which Telok replies "The words of the Athenian gadfly?" Anyone know who the 'Athenian' is?
This is all I have for now, as I just finished it, and need to let it percolate before I can post more.