The Thirteenth Sign                                    -      #      - 
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Strange carvings representing the zodiac symbols cover the walls and
converge in the middle to a carved stone with a constellation you have never
seen before.  Before your eyes, the shape wavers and beams of light shoot
out and form one giant figure.  This thirteenth constellation is a
compilation of the other twelve, ready to attack.  

A horrid creature spawned from the twelve zodiac signs and black magic, looms over you.