The Plasm Distribution System is the second system to be added and activated as part of Egon Spengler's on-going experimental equipment field-testing. During the investigation of the 5th Avenue branch of the New York City Public Library, the Rookie comes across an unavoidable patch of caustic Black Slime, which prompts Dr. Stantz and Dr. Spengler to activate the Plasm Distribution System. Once the system has been thoroughly field-tested, it is added and activated on the remaining Proton Pack units.