Secrets of Black Marsh

From the publishers blurb: Black Marsh is a large wilderness area, most of it and unknown and unexplored. Over the years many explorers have entered the marsh never to be heard from again. Those that have returned brought back tales so outrageous that people thought the explorers were insane. Rumors about the Black Marsh tell about a treasure trove hidden somewhere in its depths. Does your party have what it takes to survive this dreaded place?