SAD, One Piece Wiki

SAD is a substance produced in a lab within Punk Hazard, the SAD Production Room, and kept within a huge metal vat. It was first alluded to in a conversation by Vergo, before being revealed to be Trafalgar Law's true objective on Punk Hazard. When it was first seen, SAD was being kept in a large metallic vat hooked up to several tubes and a prominent nuclear symbol on it. After the vat holding the refined SAD had been split open by Law, the substance is revealed to be somewhat of a foamy mixture

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