Dark May Project

The Dark May Project (暗闇の五月計画) was an experiment carried out in Academy City, aimed at replicating Accelerator's powers by implementing similar patterns of ability operation.

Principles
The Dark May Project was an experiment that used subjects who were most likely Child Errors, in an effort to replicate Accelerator's powers by using a similar pattern of ability operation. This was done by referencing the cognitive patterns of Accelerator himself in order to optimize the personal realities of certain espers taking part in the experiment. Kinuhata Saiai was once a part of this experiment which taught her to use her ability as an automatic self-defense capability that activates if she is attacked, similar to Accelerator's vector shield. Kuroyoru Umidori was also a subject in the project, and apparently killed all the researchers at one point, bankrupting the project.

Saiai stated that it wasn't usual for children of the experiment to end up well, as many of them ended up in dissection tables while scientists tried to figure out in which part of the brain the personal reality was located.

One of the after effects of the project is that Accelerator's personality may be ingrained into the subject. Kuroyoru Umidori, Tsurigane Saryou, and Yuzuriha Ringo seem to be the ones to have such side effects.

Background
At some point of the past, Kuroyoru apparently killed all the researchers, bankrupting the project.

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.

World War III Arc
Although Misaka Worst hasn't warmed up to Accelerator for sparing her, the Level 5 urges her to cooperate about looking for better leads related to the parchment pieces. Worst refuses, but Accelerator reminds her that her fate as a clone will be the same because they will remain disposable unless something is done. The Third Season clone stubbornly stays uncooperative until Accelerator opens a possibility for her to be useful through the Dark May Project. Misaka Worst sees it a worthy opportunity and decides to agree.

Freshmen Arc
Accelerator told Kuroyoru Umidori that he had once eliminated Academy City's dark organization. He would like to know why dark organization still active. Kuroyoru replied with anger that not everyone in the world just get along with. Soon, Accelerator realized that she is subject of Dark May Project after observing her pattern of calculation and manner of speaking.

Jailbreaker Arc
Oumi Shuri have learned that Tsurigane's involvement of Dark May Project transformed her personality. It is unknown as to what extent the Dark May Project had changed her as Oumi Shuri could not tell Tsurigane would betray her until the moment she attacked.

Toaru Kagaku no Dark Matter
Kakine saved Yuzuriha Ringo from bunch of thugs because she is one of the survivors of Dark May Project. Yobou found out more survivors to contact but Kakine refused offer in order not to be detected. His goal is not fight with Accelerator, but want to know Accelerator's calculation pattern for unknown reason.

Known Participants

 * Kinuhata Saiai
 * Kuroyoru Umidori
 * Tsurigane Saryou
 * Yuzuriha Ringo