Plume of Dusk

Plume of Dusks are crystalline substances named after their appearance which, although never shown visually, are described to be thin and both platelike and circuit-like. Plume of Dusks are also described as vital, "similar to a living thing, yet different" as well as said to "exist in a state between mind and matter, mass and information", a description harkening back to that of the Velvet Room.

They are primarily used in the cores of the personality modules of the robotic Anti-Shadow Suppression Weapons in order to grant an awareness from which they can summon a Persona. In Persona 4 Arena, it is revealed that earlier models such as those in the twenties and below (such as Unit ) had lesser sized Plume of Dusks while later models, most notably Aigis or Labrys had full-sized Plume of Dusks. Due to having full-sized Plume of Dusks, it is speculated by the scientists in the intro of Labrys' story that such robots will develop their personalities faster like when Labrys speaks in an accent immediately upon awakening.