Suddenly, out of no where a blue... thing charged Stern with a speed and precision that rivaled that of a Vindicare Assassin. What ever it was, it hit his wrist mounted storm bolter, knocking his aim off target. It followed up by punching Stern in the torso with a force disproportionate to its size. It was enough to push him back slightly, but it didn't even dent his adamantium armor. Stern's first reaction was indigence. "You dare..... You DARE touch ME xenos?!" he shouted, his vox amplifier casting it at full volume. He saw the blue xenos conjure some sort of bone. Immediately suspicious, Stern checked his armor's readings. Stern was surprised to see warp energy around the bone staff, and residual warp energy where he had been punched. So not only was it a xenos, but a warp sensitive xenos as well. There could be only one course of action now, as dictated both by the imperial creed and the codex astartes. Stern drew his Nemesis force halberd, and activated its power field with his own warp energy. His armor began to feed his body with adrenaline, and he readied himself into a combat stance. "Xenos filth!" he shouted at the blue dog creature. "I am brother-captain Arvann Stern of the Grey Knights, and my blade will be the last thing you ever see! Now face me coward!"