Ultramarines successfully degrade ork defences on Magark

In the Vastrid subector the Imperium had begun to put together a strike force with the intention of invading the ork worls of Magark. Having secured the smaller ork system of Aspaster, Magark was the next logical target. For many centuries the orks had infested the Cerrack Nebula, and forts around the region protected the important imperial planets nearby. With the intelligence given to Lord Titus Luthor however, the Imperium could no longer simply ignore the ork threat. A Waagh! was brewing and eradicating the ork threat in the Nebula seemed preferable to waiting for the storm to break over the sector capital and it's nearby worlds.

While the army of invasion was being assembled at Aspaster, the astartes began systematically degrading the defences of Magark. This would take a number of missions, and the astartes and other elite forces were preferred to attempting to bombard the planet with the imperial fleet. The orks didn't have a huge fleet themselves, but they did have a number of lumbering roks, and the appearance of the imperial fleet too soon, would encourage the orks to construct their own vessels in response, something the orks had proven they could do rapidly and effectively.

Instead, elite raids were conducted. The first, involving an imperial knight, had been unsuccessful, but the Ultramarines launched their own attack in mid 11.021M42, evading the unwieldy ork "fleet" and landing on the populous ork world. Their aim was to establish a perimeter around a set of powerful ground based lasers, which would be a real threat to troop landers, then destroy them before the orks could organise a response. This they achieved, although the ork response was more swift than expected. The astartes chapter however were known for their technical adherence to the codex astartes, and this time it served them well. The ork leader was killed in combat, disrupting the greenskin counter attack and allowing the defense lasers to be eliminated before returning to their strike cruiser. Several more raids would be needed, but for now the operation to soften up Magark was going well.