Menhir Room                                            -      -      - 
(-------------------------------------------------)     - <---(M)---> -
                                                        -      S      -

You have entered a large room in which an enormous boulder rests.  The
boulder is blocking an elaborate archway.  Runes of power, once engraved
deeply into the arch, have been obliterated by some unknown force.  The
boulder was apparently placed in the room to block the archway...  To keep
whatever is behind it from entering the upper level of the Proving Grounds.