For catching her Yuisen, it wasn’t just that he stopped it. It’s his spell, Thororm’s Defense. Anything that meets his eyes that he’s able to percieve as a weapon loses all its power, both the weapon itself as well as any Magic behind it, all get turned to 0
So Kanzaki’s sword lost all its power and could easily be caught by Knight Leader no matter how hard she swing it:
The spike fitted on the back of the grip wasn't in the same size range as a nail.
Matching the greatsword's full length of 3.5 meters, the spike was practically a stake.
Realistically, even if the attack wasn't instantly fatal, the right ribs must have been pulverized.
The two faces hidden by the darkness were mirrored.
One was in anguish.
The other was aloof.
However,
the expression of anguish belonged to William,
and it was Knight Leader who was aloof.
While William's strike wasn't meant to be fatal, its destructive force should have been enough to ensure that Knight Leader became immobilized.
But in truth, there wasn't a single wound on him.
The spike which should have been rooted into his chest hadn't even penetrated the cloth of his suit, let alone draw a single drop of blood.
The unnatural sponge-like sensation naturally brought an expression of doubt to William's face.
(The impact was displaced... no, that can't be. Is this...?!)
"Do you know of a Norse warrior called Thororm?"
Knight Leader spoke without a change in his expression, as the spike continued to push against his chest.
"He used a magic which had the power to reduce the sharpness of an enemy's blade to zero. Thus, no attack could harm him, while Thororm's would be the only sword which could cut at the opposition."
"You, mean..."
"I have constructed a technique by which I can reduce the offensive power of any and all armaments I recognize as such to zero. And I will let you know, that it makes no distinction between science or magic. Theoretically, it can neutralize even a nuclear weapon. As for those against which it has been proven... yes, it should be able to handle something on a level similar to the slashing attack wielded by the Saint of the Far East, designed to fight divinity."
Knight Leader slowly shook his head.
I told you that I had prepared multiple trump cards, he continued.
"It is effective against each weapon for ten minutes at best. Of course, there is no need to consider arrows and bullets once they have fallen to the ground, and bombs would not suddenly explode ten minutes after their first attempt failed, though that would necessitate the prevention of any further 'explosive triggers' - not that this relates to you. In any case, I have simply created a grace period of ten minutes... but you should know well what end awaits one who presents that much time to his enemy on a true field of battle."
Knight Leader glared directly at William.
"I was subjected to a terrible ambush at Dover, long ago - it was enough so that I wished to take measures against something like this."