Horus heresy. Book 3. Legion. The battle for the "abyss". Mechanicum. Abnet D., Caunter B., McNyll G.

Not every battle of the great heresy is noticeable to the eye and falls on the pages of history. The warriors of the mysterious alpha Legion, who previously exterminated the enemies of the emperor not only with blades and guns, but also by lies and deceit, just as inconspicuously and insidiously turn against him. The adherents of the mechanicum, the adherents of the mechanicum, sides the Horus, who presented the dark gifts, and create unique guns of war - from combat vehicles with an artificial mind to starships of unprecedented power for knowledge. When the internecine battles cover Mars itself, truths buried millennia, capable of shaking the whole galaxy...