Arthurius made his way to the bridge, where he was certain the Daemons and Traitors would attempt to take over as soon as they could. Unfortunately he was slowed by Traitor Guard and instead spent his time instead plowing through the Men of Chaos. Where he swung, limbs and lives were lost, both meaning less than the feeblest old man on Necromunda and the various Hive Worlds scattered throughout the Imperium. He finished off the last of the group and continued on, minor scratches on his armor being his only wounds.
The Epistolary arrived at the bridge, just after the Traitor Marines had begun pouring through a new gate. Two were killed as he charged, one from three shot of his plasma pistol, and one from the tiniest scratch caused by the force sword he held in his hand, glowing with power.
"Back to your Masters you traitorous scum."
He clashed with two others, neither side gaining the upper hand until he unleashed his powers, a risky move considering the Chaos portal a few steps away. Closing his eyes and trusting in the Emperor to keep him defended the few hearbeats it took to conjure the power capable of what he intended to unleash. A glow started from his eyes as he opened them, quickly engulfing his armor and body in a blue almost white, a barrier against the weapons of his opponents. He stepped forth and allowed an attack through, which connected with the light and bounced back, no damage to the armor at all.
"You are powerless against the Imperium, Traitor, now back to your dark pit from whence you came! Eternal torture is your reward, scum."
He slashed out, the armor breaking against the strength behind his strike and a flash from within the helmet as the sword bit into his body, again killing him instantly. A spin and he crossed swords with the remaining Marine he'd been fighting. Neither giving ground, both equally matched. Arthurius had dropped his pistol in favor of testing his strength against the Traitor Marine. Slowly but surely his opponent began losing, the Dark Angel stood his ground, his opponent weakening as time went on, Arthurius only keeping strong against his opponent. Then the Red Corsair pulled back suddenly, leaving the Epistolary open to attack for the briefest of moments, and the power sword he wielded came down for a killing blow to his neck, only to be stopped by the light outlining his body, leaving nothing but a scratch on the armor underneath. The Librarian retaliated by driving his own sword through the armor and body of the Marine, and removing it, leaving him to slump backwards, dead.
There was still work to do however, and Arthurius knew it. He retrieved his pistol from the bloodstained deck and turned to face the remaining Traitor Marines on the bridge.