A bizarre result of zombies attempting to breed, the development of a Zombie's embryo into a Beeblezug is triggered by a genus of social fly that has evolved a symbiosis with the undead. These degenerate insects spend their entire life cycle in a maggot-like stage, breeding rapidly in the Beeblezug's body and functioning as a part of its digestive process; able to drill rapidly through even healthy flesh, the maggots are violently regurgitated by the Beeblezug to reduce its food to mush before reingestion. The monster may even project a thin stream of maggots up to several yards away, sometimes landing birds as they fly overhead.

  Due to the countless bodies writhing in its flesh, the Beeblezug is constantly twitching and contorting, almost as though dancing. It makes a heavy slurping sound as it prepares to attack.