Books in the Death's Head series in order

The Aux have been dropped on a far-flung planet called Hekati, only it's in Uplift space and not really a planet at all. As for their mission, it's so damn secret that General Jaxx hasn't even told Lieutenant Sven Tveskoeg what it's about.

As this stubborn, insubordinate son-of-a-bitch feels the first lash fall, he hears the desert tribes attack, and watches as they slaughter his comrades before they can execute him. Rescued from certain death, Sven joins the tribes. Sven feels he's a pawn in a deadly game, and pawns have an unfortunate habit of being sacrificed.

Lieutenant Sven Tveskoeg is in disgrace. His victory on Hekati, and the emperor's favour, have turned his patron against him: General Indigo Jaxx wants Sven dead.