sentences:  Later, Gerhart is part of the assault on Magnum Christi, a minor moon on a back-water planet that had been taken over by the forces of Chaos.The Chaos forces flee, despite having both the troops and the tactical positions to drag out the fight.Gerhart and other fellow Space Marines follow the retreating forces of Chaos, only to find why Chaos had invaded the planet; Two Titans, legendary machines of war, have been found by the forces of Chaos.