Wraith Roaches mark the first appearance of a "swarm" as a D&D monster, in the Dark Magic in New Orleans adventure. The concept was later worked into the 3rd Edition version of the rules. DESCRIPTION Wraith Roaches are the result of a bizarre experiment by an evil priest, using insects that are ubiquitous in warm and humid regions. Originally created as guards, the progeny of these mystical creatures has spread, thanks in part to its unique way of propagating.