Celestia followed the Commander to the gleaming steel door.  He produced a complicated key, took it in his teeth, and inserted it into matching keyhole.  He looked over at one of the unicorn guards, and nodded.  The guard nodded back, and his horn began to glow a pale blue.  The commander gave the key a twist.  Tiny machined levers could be heard maneuvering out of place, along with the deep sonorous grinding of several large steel deadbolts sliding into an unlocked position.   