It was a function to build the brain.
And because of that, there was a consideration to allow residents of Academy City to use it.
After that, that inexplicable power was activated. Kihara Kagun was involved in a rather destructive explosion.
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"In the beginning, this was an ability to create a brain, a side effect of that experiment. That experiment itself was a failure. It's true that the brain is part of the body. Simply put, the brain can't operate as a brain if it doesn't go through my body."
That smile was lacking, but after a while, the face would be complete.
"Well, I can only use the power at Level 2 or Level 3. The initial driving concept was that if I want to hold people up and punish them, I just need about five people. I can also use the wave-shaped attack to peel off flesh and blood from the bone. I'm really fine with that, but the effect was rather good, wasn't it?"

Toaru Majutsu no Index New Testament vol.4 main.31