Cremutus and Chelkar
The human ratings did their best but they were untrained in frontline combat while the armsmen were almost to a man rendered incapable of aiding the battle in any meaningful way. The officer tried to rally them and seemed to hold the ratings there but as Cremutus stood resolute an imposing figure he indirectly rallied the forces of chaos who aided in pouring fire on the defenders while in side passages and other minor fights warriors of chaos took to heart the fact that they were winning and would impress themselves upon their gods. From above lasrounds rained down on defenders who could find no cover from his shots and further panicked the already near broken men of the Imperium. With every passing salvo of fire the Imperium firepower lessened, none would even dare to try for the heavy stubber that had moments ago held back the tide of chaos so well for it's exposed position doomed any who would try for it now.
Seeing the flanks collapsing and the best of his men unable to fight back while the remainder barely holding on while dieing and unable to even harm the monster across the bay from them the officer gave the only order he could. "Fall back, all men fall back to form new defensive positions," he fired his pistol towards Cremetus as more of a show of solidarity than any real chance of harming him. Looking up towards the cat walk he saw Chelkar as well and made sure to fire a parting shot at him as well to let him know the officer was aware he existed. Relieved of their order to hold the line though it was irrelevant to the ratings who fled from the frontline towards the hatches leading out of the bay. They were potential killzones they could hold if they could somehow find the armaments to hold them with and could rally from what was rapidly turning into a panicked retreat.