A One-Round Living Greyhawk Verbobonc Regional Adventure
From the introduction:
An unusual request, a secret meeting, and a hamlet that isn't on any maps. You've been selected to assist in investigating just what has the Church of Saint Cuthbert worried... and the Viscount thinking there is something far more sinister going on.
An adventure for characters level 10 to 17.
[Player character] combatants that are members in Verbobonc regional meta-org's, or who are mercenary in nature, are highly recommended.