uses iron sand to react to super sonic person

Brunhild Eiktobel could reach a top speed that exceeded the speed of sound.
And she brought out that top speed from the very first step.
By the time the explosive noise rang out, it was already too late.
From the perspective of one’s bodily senses, Brunhild seemed to just disappear. And
since she was moving faster than sound, one could never react in time based on sound.
Brunhild Eiktobel charged up to a point right in front of Mikoto and vigorously swung
up the claymore hanging down from one hand.
She also twisted her wrist to lay the giant sword down flat as she swung it.
Normally, this may have been an attempt to not hit one’s opponent with the blade of the
sword. However, the situation here was different. Brunhild Eiktobel could move at
supersonic speeds and the claymore she held was like a giant sword made by attaching a
grip to a metal sheet.
By laying the blade flat, she could use it like a giant fan made of steel.
An overwhelmingly violent fan that used the massive shockwave created when an object
moved at supersonic speeds.
That would end it.
Not only would it crush the girl’s fat and muscles from the outside, but her eardrums,
lungs, and trachea would rupture from within.
However…
“Damn you!!”
“!?”
She reacted just before it hit.
A dull noise came from below their feet. The ground below moved. The road at the top of
the overpass was made in blocks that included the supports below. The girl controlled
one entire block with magnetism to tilt it like a seesaw.
This caused Brunhild’s aim to be off with her claymore strike and the sonic boom flew
off into the distance. All the glass in one of the buildings alongside the road was
smashed to pieces.
(A broad-use electric type? So did she use some kind of radar? No, this is…!!)
Iron sand had been thinly spread all across the road surface.
Even if Brunhild Eiktobel’s movements exceeded the limits of the girl’s kinetic vision,
she could clearly see what path Brunhild had taken thanks to her footprints.

- New Testament Volume 6 Chapter 7 Part 7