Horus Heresy: Solar Auxilia...
The Solar Auxilia are the most elite division of the Imperial Army, mortal soldiers trained to fight in alien atmospheres, toxic death zones, and even the cold vacuum of space – the most hazardous battlefields of the Great Crusade. Equipped with sophisticated wargear and sealed environmental armour, the Auxilia are recruited from across the Imperium's many conquests, chosen for a mix of skill, discipline, and raw aggression. As the Age of Darkness sweeps across the stars, the countless cohorts of the Solar Auxilia must each declare their allegiance – honour their Warmaster, or stand with their Emperor?