Grinding her teeth, Saber calmly assembled the puzzle in her mind, and the series of hardly believable circumstances pieced themselves together.

Her armor should have blocked Lancer's spear. Nevertheless, the tip of the spear had Saber's blood on it.

And— right now, Saber's armor is the same as ever, without a scratch.

To make a practical guess, just with the spear coming in contact, the blade passed through the armor as if it had vanished.

Saber cannot dematerialize, but she can materialize her battle outfit and then cancel it. In other words, Saber's armor is knit out of prana, and it is not material in the present reality like the clothes Irisviel bought.

Furthermore, it was incomprehensible that Invisible Air could be cracked... The contact with Lancer's spear had created a fissure in the bounded field that generated the wind.

"... I see. I figured out the mystery of your spear, Lancer."

Saber murmured with a low voice. She reflected once more upon the toughness of her formidable enemy.

That red spear can cut off prana.

Nevertheless, it's not so powerful that it could break or cancel the source of the magecraft. Saber's armor is still fine, and Invisible Air is still functioning correctly. The spear is effective only the instant it hits the blade.

Apparently, at that instant, it cuts off the flow of prana, and renders it powerless.

Indeed it is not a Noble Phantasm one could be proud of its destructive power, but it has an ability that can be quite a threat. It is not an exaggeration to say the quality of a Servant's weapon is determined on the prana or the magical abilities it carries. But in the hands of this Lancer, it can be predominant against a Servant who finds pride in the power of his armament.

"You'll have to give up on the protection of your armor, Saber. In front of my spear, you're as good as naked."

- Fate/Zero: Act 3, Part 5