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This adventure takes place in the River Quarter of the Free City of Greyhawk and was printed in Dungeon Magazine #114. The adventurers investigate matters relating to the Cult of Vecna, which leads them to the Tomb of Blood Everflowing in the Cairn Hills. The Green Dagger hideout is an abandoned building with bandits in waiting. Barge End is the docks where a chase scene ensues.
Cartouche heraldry by Anna Meyer, used with permission. Visit her page here: https://www.annabmeyer.com/