@homura_kitsune: (and everyone else, but I'm pretty certain this is the only direct attack I have to respond to, at the moment; please sing out if I am mistaken)!
Pain, at least conventional pain, had long ceased to be a meaningful part of Vitus' existence. His unliving, necrotite-infused body did not register agony from physical damage as it would have when he was a living being; it was often little more than a passing thought, an inconvenient reminder that he would need to attend to repairing that damage at some point. The attack on his person, while inflicting a surprising amount of damage to his body, did not cripple him with the torment that would have wracked a living target.
That said, his sense of pride had, if anything, been enhanced by his condition. Even in life, none had dared to attack him in such an...irreverent manner; that some inhabitant of this backwards, water-logged piece of cosmic detritus would have the audacity to do so was simply unacceptable. His vision grew as red as his eyes blazed with fury, lips pulling back over predatory fangs in a snarl so reflexively primal that it would have given a wild animal pause.
However all the arcane and technological enhancement in the universe did not alter the laws of physics, The uncanny impact of the blows tossed him about like a rag doll, and left him in no position to respond to the attack, or evade the destruction of the building upon which he stood. In a matter of seconds, the cosmic vampire found himself in an improvised tomb consisting of tons of rubble.
Had he been alive, the attack would have killed him a dozen times over. As it was, he was going to require time and sustenance to repair himself. Rather than attempt to use his telekinesis to dig his way free, he once again faded into mist, which seeped downwards into the damaged foundations of the city until it located a easier means of traversing: sewers and subway tunnels. Here, he would rest and feed, first upon the omnipresent vermin, and then upon survivors who had fled below ground to evade the attack on their city.
The image of his attacker burned in his mind as he slowly regained his strength. While he may have been removed from this battle long enough to no longer factor into its outcome, he would find the one who had dared to oppose him in such a mocking manner.
He would find him, and use him to redefine the very notion of suffering...
Back on the surface:
If the Deathborn even registered the catastrophic removal of their commander from the battlefield, they gave no outward indication. They had their orders, and carried them out like the malevolent synthesis of machine and living mind that they were. They continued to inflict damage on the city, even as the initial shock of the assault wore off and their offense began to lose momentum. For all the civilian casualties that had been inflicted, most of the humans able to do so had fled the streets, finding hiding places that, for the moment at least. made them unsuitable targets. Above, the Strikers' numbers began to dwindle, as the Earth's defenders rallied.
Where a conventional military might begin to fall back, however, the forces of the Imperium pressed coldly onward, driven by their programming to act as ordered. Only new orders or their own destruction would deter them, and it seemed likely that any further orders would not be forthcoming, barring the appearance of a new commander.