152-page hardback book.
Background and lore: Information on the Mechanicum, their organisation, and examples of their forces.
Rules and unit profiles: A guide to army building, plus rules for units, weapons, and Wargear available to the Mechanicum in The Horus Heresy.
High Tech Arcana: Rules and Detachments for the following faction traits: Archimandrite, Cybernetica, Lacrymaerta, Myrmidax, Reductor, Malagra, and Macrotek.
Cybertheurgic Rites: Additional rules that reflect the esoteric ways in which the Mechanicum does battle.
Machina Malefica: Unit profiles for creations infused with the dark energies of the Warp.
Visual showcase: Colour schemes for infantry and vehicles, and a gallery of stunning miniatures photography for the Mechanicum.