|This article is about the Imperial Confessor, for the Dark Apostle see Marduk|
Marduk was an Imperial Arch-Confessor. In response to the Orpheus Revolt, Marduk declared a War of Faith to reclaim the Orpheus Sector in the Emperor's name. Marduk claimed that the God-Emperor himself warned him of a great and terrible threat to all Mankind "Rising where the light of Orpheus falls forever into shadow". Gathering hundreds of thousands of followers, the Arch-Confessor proves to be a figurehead and rallying point for the Orphean Campaign and helps stem the tide of heresy.
Later while leading an attack on the final Chaos stronghold of Colkasth, Marduk and his army disappeared after encountering an unknown Xenos threat which reduced both Imperial and renegade forces on the world to radioactive waste. The Holy Synod later declared him a martyr and elevate him to a Saint, renaming Colkasth as Saint Marduk's Bane.