A pillar of light shot out from within the cracks.

It looked something like a laser beam about a meter across. The light was so pure a white it looked like it had been melted by the sun. The instant it shot out at him, Kamijou thrust his battered right hand out in front of his face.

[...]

(This isn’t just a large mass! Each individual piece of light is something different!!)

It was possible Index was using her 103,000 grimoires to use 103,000 different types of magic at the same time. Each individual grimoire held instant death and she was using them all at once.

Toaru Majutsu no Index vol.1 ch.4