prison

Master-servant relationship? Master-servant… master-servant… Nnn, nnn? Nnnn?… Um! I'll stop thinking!

For me now, the king is you! My loyalty from my heart.And the spice with the name of affection! I can't help making you nervous to my heart's content and manipulating you!

A sealed away second Noble Phantasm.
One that invokes the power of the Hippogriff that Astolfo uses when he's summoned as a Rider.
An imaginary numbers-like existence that’s everywhere and nowhere at the same time throws the enemy camp into disorder.
Specifically speaking, Astolfo will turn into multiple copies, and whether the real one is there or not, he won’t receive damage.
Even worse, after a certain period of time has elapsed, Astolfo will rapidly increase in number.
The sight of having close to a hundred Astolfos clamouring and squealing in a rave might be the worst nightmare possible for a specific group of Servants.[2]