precog

Accelerator was shocked at first, but soon figured out his tactics from the situation.
From previous reports about Academy City’s #3, Railgun, who Accelerator had faced off
against before, in the rumors associated with the Railgun, there was one saying that an
unknown Level 0 existed that could match against the Railgun using only his right hand.
This raised many questions.
For example, even if a right hand that could negate any ability exists, how could the one
using it match his opponent’s timing?
A railgun attack was over three times the speed of sound, and lightning strikes were
even faster. Even with a method of defending himself, to be able to time it right was
extremely difficult. Even missing the timing by only an instant would probably result in
death. In that situation, how could the he easily negate every single attack?
From the current situation, Accelerator could make a rough estimate.
In other words.

Precognition.

For example, when the Railgun used her ability, she would give off weak magnetic fields
and electromagnetic waves that would make the metal items around her resonate.
Because of the eventual large explosion, the Railgun herself probably wouldn’t notice
these tiny vibrations like an earthquake’s precursor. It was similar to the elementary
school experiments in which you would spread iron sand to be able to see the invisible
magnetic force. So, because of the “An Involuntary Movements”, there would be hints to
when the Railgun would attack.
Of course, that was not all.
That was not the only kind.
Even though her ability was more common compared to Accelerator’s ability, she was
still the #3 Level 5 of Academy City, and shouldn’t be blocked that easily.
There were probably other reasons as well.
For example, the lightning strike.
If it was only high voltage electricity flow, by extending his right hand the lightning
would be attracted onto it, with the right hand acting like a lightning rod.
Also, the iron-sand sword.
Apart from the sword in her hand, the iron sand around her would also change shape
due to the magnetic force. In other words, a visible magnetic path would be formed that
could be used to predict where the strike would end up. Depending on the situation, he
could even negate the sword without coming in contact with it just by touching the iron
sand around him.
Sometimes the path to victory would change.
Was it using the most powerful ability one possessed, or the aftermath from that ability?
According to different tactics used, the path to victory changed along with it.
What was most important wasn’t whether there was a chance for victory, but to never
rely on only one form, and look at the problem from many different viewpoints. Above
all, look for the best method to resolve the current situation. Even against the same kind
of espers, the same kind of tactics might not be suited to be used. Even if it was just
lightning strikes, depending on how it was used, different tactics may have to be taken.
Because of this, battle tactics were always changing.

By depending on the defense from the ability to negate any ability to avoid being killed
instantly, to buy time and use it for maximum gain. By experiencing the impacts on
one’s own body and using that data as the basis to find the best way to get out of the
situation alive.
Just having brains wasn’t enough.
Just having the power wasn’t enough.
Only by combining the two it was possible to barely succeed.
In the situation where death was only a hair’s-breadth away, having the courage to keep
his body and thoughts moving probably helped a lot as well.
However.
The Level 0 probably didn’t realize it himself.
How to use his ability in its fullest potential, using the aftermath as a basis, and then
change tactics to fight according to the situation. He was probably just combining those
with his reflex. As for the Railgun making everything made of metal vibrate around her,
he probably didn’t take note of it explicitly but took it in using his peripheral vision, and
processed it deep inside him. So, success was not guaranteed. On the other hand, if he
actively tried to take note of these things it was more likely to fail.
However.
Just taking Accelerator’s attack and surviving was exceptional in terms of battle ability.
Even if anyone else had this power in their right hand, how many could get the same
results?
Taking only the supernatural abilities into account, he definitely couldn’t be called
“strong”.

- Toaru Majutsu no Index Volume 20, Chapter 4 Part 5