The Space Marine Legions of the 31st Millennium field a diverse and powerful array of genetically enhanced warriors and advanced war machines superior to any other military force in the galaxy. As an age of darkness descends upon the stars and the fires of rebellion grow out of control, the armies that forged the Empire turn against each other in an apocalyptic civil war - the Horus Heresy.

Of the eighteen Legions of Space Marines, half betrayed their oaths. As defiant servants of the Warlord, these Space Marines gather their forces to overthrow the Emperor and conquer the throne world of Terra. In the chaos of the Horus Heresy, the Traitor Armies unleash powers and ambitions beyond mortal understanding and wage bitter war against their former brethren - those who honor their oaths and stand at the Emperor's side. Through the determination and fury of these rebellious warriors, the fate of the Empire and humanity itself will be decided.

This book is an essential guide for anyone wanting to command a Traitor Legiones Astartes force in Warhammer: The Horus Heresy. It contains all the rules you need to use all of the units and formations available to the Traitors, from the core units and weapons used by each Space Marine Legion to specialized rules for each of the Traitor Legions - including Rites of war, unique equipment, the special units of each legion and their legendary Primarchs.

In this 352-page hardcover book you will find:

- Rules and unit profiles for every Traitor Legiones Astartes unit, weapon and equipment in Warhammer: The Horus Heresy
- Legion-specific special rules, Warlord Traits, Reactions, Rites of War, equipment, unit profiles, and unique characters for each of the Traitor Legions: Emperor's Children, Iron Warriors, Night Lords, World Eaters, Death Guard, Thousand Sons, Sons of Horus, Word Bearers, and Alpha Legion
- Profiles for each Traitor Primarch: Fulgrim, Perturabo, Konrad Curze, Angron, Mortarion, Magnus the Red, Horus the Warlord, Lorgar Aurelian and Alpharius
– A gallery for each Traitor Legion with heraldry, color schemes for infantry and vehicles, and a small gallery with impressive miniature photographs

To use the contents of this book, you will need a copy of the Warhammer: The Horus Heresy – Age of Darkness rulebook.