Chaos Marine Warband

The Traitor Legions are comprised of the original 9 Space Marine Legions that betrayed their oaths of loyalty to the Emperor of Mankind during the ancient civil war called the Horus Heresy more than 10,000 standard years ago. The Traitor Legions were led by the Warmaster Horus Lupercal, once a Primarch of the Imperium and the Emperor's most trusted friend, son, and adviser before he was corrupted by the promises and lies of the Dark Gods and his own inner flaws.

The Traitor Legions are the most powerful component of the Forces of Chaos. The flesh and Power Armour of these Heretic Astartes warped and twisted into new, darker and inhuman forms under the influence of the Chaos energies they were exposed to, and came to embody the corrupted Astartes' new allegiance. Following their defeat during the final epic confrontation, known as the Battle of Terra, the Emperor pronounced judgement upon the Traitor Legions. They were declared Excommunicate Traitoris.