From the front of the book:

For years, the forces of Elemental Evil remained quiet. Adventurers picked through the ruins of the moathouse again and again, each time finding little more than dust and the remains of epic battles of days long gone. Thus, you aren't surprised that your quarry, a murderous orc cleric of Iuz named Tahrg Soulhammer, fled there when you nearly caught him. Tahrg is intent on making a last stand, and you are more than happy to provide him with one. Yet, you can't help but wonder if there's more here than meets the eye. Tahrg is too clever to trap himself in a decrepit old ruin. Does the moathouse still harbor some dark evil? A one-round, one-shot adventure for 5th level characters.

User notes:
This adventure premiered at Origin '08 and was later made available for download via the RPGA.