The Battle for Black Reach was an Imperial military campaign undertaken in 855.M41 by the Ultramarines 2nd Company under the command of Captain Cato Sicarius against the WAAAGH! Zanzag unleashed by a horde of Goff Clan Orks under the control of the Greenskin Warboss Zanzag. This campaign was fought upon the Hive World of Black Reach located in the system of the same name in the Imperium's Ultima Segmentum. This campaign is considered a textbook example of how the Adeptus Astartes serve as a potent force multiplier whose planetary assault tactics and skill at mobile combat can turn the tide of battle against a much more numerous foe.