Imagine Breaker

Imagine Breaker.
Esper powers ranged from the ones mocked on TV to the ones established with
numerical formulas in Academy City. Anything using that kind of supernatural power,
even if it were part of God’s system, would be negated without question by that
supernatural power of his.
As it was supernatural in origin, even that girl’s Railgun ability was no exception.
However, Kamijou’s Imagine Breaker only worked on the supernatural power itself.
Simply, he could negate an esper’s fireball, but he was still vulnerable to the concrete
shards broken by the fireball. Also, the effective range was only his right hand and wrist.
If the fireball hit him anywhere else, he would be burned.

- Toaru Majutsu no Index Volume 1, Prologue