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Toaru Majutsu no Index
Academy City Invasion Arc
- Main article: Academy City Invasion Arc
During a conversation between Yomikawa Aiho and Accelerator about his past and the Special Ability Institute, Produce is mentioned as one of the research teams that used underhand means to acquire Child Errors for experimentation.
Battle Royale Arc
- Main article: Battle Royale Arc
When Kakine Teitoku brought up Kinuhata Saiai being a former test subject of the Dark May Project, she mentioned that she was super happy compared to the test subjects of Produce who had their brains chopped up like a Christmas cake in order to figure out where in their brains their Personal Realities lay.
Toaru Kagaku no Accelerator
- Main article: Necromancer Arc
Five years prior to the current year of the timeline, Hishigata Mikihiko's research team had spent months testing where in the body esper power reside. From limbs to brain parts, they had removed subject's body parts to prove their theory. As the body grew smaller and smaller the output of the power dropped. Applying this finding in reverse, Hishigata conceived the idea of reinforcing and expanding the body to strengthen its power, which led to the development of the Coffins.