A One-Round Living Greyhawk Furyondy Regional Adventure
From the introduction:
Across the lands of Furyondy, a call to arms is being made to all available military personal, including the Furyondy reserves as well as to mercenaries (adventurers) to come to Fort Belvor to defend the eastern front. As for the mercenaries, a special task needs to be handled for the Military. Pay is optimal and tax-free. Mercenaries with infamy in the Furyondy Military are not welcome.
A dangerous Military adventure for experienced characters of at least 5th level.