Since it was a decoy facility, the wide area had no power generation equipment inside. The area was large enough to play a game of American football in and it contained nothing anyone could hide behind. Normally, it would have seemed a rather lonely place with just two people inside.
But that was not the case.
A thick “presence” seemed to fill the entire area.

______________________________________________________________

Kakine Teitoku.
Dark Matter.
Academy City’s #2 Level 5.
That symbol of his power that was scattered chaotically through the vast area, seeming to cover every inch, could likely not be so much as scratched even with standard machine tools

Toaru Majutsu no Index New Testament, vol. 5 epilogue