Dungeon Magazine #71
An adventure entitled Dark Magic in New Orleans, written by Randy Richards, appeared in Dungeon magazine #71 (Nov/Dec 1998) in the Masque of the Red Death setting. The adventure concerns the machinations of Voodoo King Doctor John and Voodoo Queen Marie Laveau in 1890s New Orleans. The players must discover who is behind a series of murders in old New Orleans, while avoiding their own deaths. The adventure introduces players to wraith roaches, zombie animals, undead snakes, half-gators, and evil trees.
The adventure's one claim to fame is that is contained the first appearance of a "swarm" as a D&D monster. The concept was later worked into 3rd Edition D&D.