Liberation of Dustbowl

The Liberation of Dustbowl was an Imperial excoriation campaign conducted by the newly incepted Dawn Guardians Space Marine Chapter, a recently created Ultima Founding Chapter comprised entirely of Primaris Space Marines. This campaign was a part of the much larger Indomitus Crusade led by the Lord Commander of the Imperium, the returned Ultramarines Primarch Roboute Guilliman.

Background
With the destruction of the fortress world of Cadia by the Forces of Chaos of the 13th Black Crusade, the Imperium was ripped in twain, separated by a massive tear in reality which came to be known as the Great Rift. With the formation of this massive warp rift, which stretched from the Eye of Terror all the way to the Eastern Fringe, the Forces of Chaos and legions of Daemons poured forth, and began the massive invasion and slaughter of thousands of Imperial worlds. Separated and cut off from the rest of the Imperium, these worlds were forced to defend themselves against the neverending onslaught of the encroaching Forces of Chaos.

The Dustbowl was one of several Imperial worlds in dire straights - cut off, alone and without outside report - forced to defend themselves against the neverending tide of filth and madness that continuously assailed their world. Though at first successful, they proved no match for the bloody-handed and merciless Heretic Astartes of the Night Lords Traitor Legion. These vile servants of Chaos Undivided proceeded to cast a pall of fear and dread, as they began to broadcast the screams of tortured and dying souls across the planet's vox casting system. The planet's citizens barricaded themselves in subterranean bunkers in an attempt to protect themselves from the predations of these merciless killers. But to no avail. In short order, the Night Lords proceeded to commit atrocities and massacres on a planetary scale. Mounds of the dead and the dying hung from city walls and the tallest spires of the various cities of the planet.

The slaughter of Dustbowl's population was only halted by the timely intervention of the Dawn Guardians Space Marine Chapter, which struck like a thunderbolt from the heavens. Within a matter of weeks, the Primaris Marines managed to isolate and cut off the Heretic Astartes from one another. The Dawn Guardians' Vanguard drew out and destroyed the remaining enemy at their leisure. Though the Chapter ultimately freed the planet from the clutches of the insidious Night Lords, their victory was a pyrrhic one at best. When they investigated the subterranean bunkers of the various cities' bunker complexes, they found nothing but a bloody abattoir. They eventually notified the local sector command of the massacre that occurred on Dustbowl. The Imperium would later cleanse the planet and re-colonise it with Imperial citizens from outside the sector.