Desperate Times Call For Desperate Measures

To defeat Horus and his fellow traitors wouldn't be easy. While the Emperor answered Horus' open challenge at Istvaan III by dispatching seven of his sons to deal with their errant brothers, the Imperium dispatched a battle group of the best forces on hand at the time to deal a blow to the traitors by attacking a Dark Mechanicus Forge World. The Dark Gods have other plans.