It is revealed in full in episode 65 though it is ultimately responsible for the events that occurred from episode 59 to episode 64 as well. This was used to create a phantom army that could hold off the combined power of Alviss, Jack and Nanashi, as well as creating an entire replica of Tokyo including believable imitations of Koyuki, Kotomi, a replacement older sister for Dorothy and a white-hatted damsel for Alan. Babbo and Alan both believe that Plenu Ryunu eventually gained a will of its own, much as Babbo did, but in a different way.