Novella involving an Adeptus Mechanicus and the remains of a Tau force. The Imperium and Tau Empire both fought over the world more as a distraction than anything serious. These are the remains of the invading forces. The Magos wants something while the Tau want to be left alone.
Much as you expect with the Tau being the designated fall guys in such a novel. A large question remains at the end which probably will never be answered.
A fun read but more showcasing the Skitarii as you'd expect as it's their story. A nice push towards a more contemporary electronic battlefront rather than the more common WW I/WW II approach. Would have liked the Tau to be a bit more competent but, as it was stated, these were the remains of a not particularly able bunch to begin with.