The Guardians of the Mysterious Golden Throne

The Indomitus Crusade has begun and the Avenging Son has taken thousands of Guardsmen regiments with him leaving the Throne World defenseless. A mysterious gate appears in Holy Terra and a new threat pours out. With Terra's remaining defenders stretched out battling cultists all across the globe, it is up to the Adeptus Custodes to go beyond the gate and explore this new world.