A Twisting Tunnel                                      -      N      - 
(-------------------------------------------------)     - <---(M)---> -
                                                        -      S      -

As you walk through the murky tunnel, your lungs fill with dust and ash,
your face becoming flushed from the intense heat.  The tunnel continues
southward apparently toward the source of the heat while a hint of fresh air
wafts in from the north.  
A cloud of vampiric mist swirls around you hungrily.