Hatsuya Kaitabi
Kaitabi Hatsuya is a character from the Toaru Kagaku no Railgun side-story. He's registered in Academy City's databank as a level 2.
Hatsuya is the culprit of the Graviton bombings in the series' Level Upper arc. His own powers were elevated to be closer to that of a level 4 than his level 2 status registered in Academy City's databank.