A Carven Alcove in the Crystal                         -      -      - 
(-------------------------------------------------)     - <---(M)---> -
                                                        -      S      -

You can tell this cavern was made intentionally.  The crystals here have
been shattered, and fractured in what appears to have been an attempt to dig
a tunnel.  As you test the strength of the crystals with your blade, you
realize it took something much more powerful than a natural force to break
these crystals.  You hope that whatever it was has given up on digging.