Fortunately a small force od Adeptus Custodes remained attached to the imperial forces in the Mordecai system and offered to carry out the direct assault. Kutuzov then placed his best mechanised regiments behind this force in the hope of a breakthrough towards Fort Parganath if the Custodes found the defences at Nazugral weak.
The Custodes force smashed their way through the thin defences around the city but then found themselves face to face with a daemonhost of Slaanesh and Tzeenth. It was then the Imperium realised the forces of chaos had feigned weakness in order to trap the imperial army in a disastrous battle within the city. They had not however reckoned with the Adeptus Custodes, and the Emperor's finest troops smashed the daemon horde although this came at the expense of the death of their commander. Within days the daemons had been eliminated and the city had been claimed for the Imperium, but hopes of a breakthrough had been dashed for the time being.