Misaka Mikoto "Railgun" was chosen for the Sisters project who cloned her. But she's ranked #3 among the level 5 espers. Why wasnt rank #2 Kakine Teitoku chosen instead, or even rank #1 Accelerator, in the case the original objective of the project wasnt to turn Accelerator into a level 6?
if I remember correctly the electric powers allowed the clones to form "the misaka network", so they can learn from the previous battles and get stronger over time.
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