knows antiflight curse

Kanzaki Kaori referred to that.

There was one legend about Peter, one of the twelve apostles. He had confronted a magician named Simon Magus who was famous for trying to buy sacred acts. When Simon had freely flown through the sky, what had Peter said?

It was...

"Oh, demons carrying this magic user, promptly let go!!"

Flight was prohibited.

That barrier existed for all magicians living in modern times.

That means of interception had spread too far due to it being simple yet both powerful and effective, and due to it being based on a famous story. Thanks to that, humans were restricted by the fact that they would be brought down the instant they tried to fly without wings.

(I can't allow myself to be led astray.)

That magician's strange appearance had led to her forgetting something very basic.

The Throwing Hammer was not a spiritual item or a weapon. It was a living human being.

A voiceless voice let out a cry that was something like a shock-wave.

The perfectly controlled giant circle was crushed in an instant. The Throwing Hammer lost control and slammed into the fortress with a high voltage current trailing behind it. When it hit, a massive amount of sparks exploded out, but it was nothing compared to the destruction that had been about to be fired.

***
With a sound like plastic boards folding, the Throwing Hammer changed from the flat plane back to the cube. It gave up on flying and seemed to be trying to roll away from Kanzaki.

But it was no use.

When the magician Simon had been brought down, he had died. For magicians, obstructing the opponent's flight was not just something that brought the opponent's altitude down to zero. The effects depended on what part of the story about Peter was being most strongly emphasized, but there was always something more than the simple damage from the fall added in.

As such, the expanded cube was unable to return to the proper cube.

- New Testament Toaru Majutsu no Index Volume 2 Chapter 4 Part 8