348-page hardback book.
Background and lore: Information on the Legiones Astartes, 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 Traitor Legiones Astartes in The Horus Heresy.
Legion-specific special rules: Unit profiles, Detachments, Gambits, Wargear, Faction Abilities and Reactions for each of the Traitor Legions.
Primarch profiles: Rules to unleash Primarchs.
Visual showcases: Heraldry markings, colour schemes for infantry and vehicles, and a gallery of stunning miniatures photography for each Traitor Legion.
Loyalists in the midst: Rules for Saul Tarvitz and Garviel Loken so that you can use forces still loyal to the Emperor.