Rob Sanders
Tech-Priest

Magos-Explorator Omnid Torquora orchestrates war against the Iron Warriors for control of a long-lost forge world. With skitarii legions and maniples of battle-servitors and robots at his command – not to mention the mighty god-machines of the Titan Legions – victory is within his grasp… until treachery threatens to end his dreams of conquest.
Warhammer 40k
novel

Also in:
Adeptus Mechanicus