The door began its slow inward glide.  The ringing paused.  When the gap was big enough, Celestia slid inside, followed closely by Luna.  The creature lowered his chair and took a look at the new arrivals.  He had shed his camouflaged outer blouse in favor of the olive drab t-shirt beneath it.  The shirt was dotted with bloodstains and its fabric was torn in several places, presumably from shattered glass.  His eyes flicked from Celestia and Luna to the door.  Luna followed his gaze and quickly moved to block the exit.  The creature merely chuckled, shook his head, hefted the chair behind his head and swung it into the barrier.  