Send In The Clowns by Mike E. (member name unknown)
The PCs have been on the trail of a mysterious, important artifact, and have managed to track it to a travelling carnival. After fighting their way through murderous clowns, exotic animals that the clowns have let out of their cages, and other circus performers (snake charmers, fire breathers, etc), they have come face to face with the leader of the clowns, Jas-Tor.