Saber - Arrow poison

Later all the figures had coalesced into one... but there was the arrow that had knocked away the arm of her Delusional Heartbeat: Zabaniya. That Saber did not appear to have fired it. Furthermore, the arrow had been laced with a powerful poison. Because she had acquired resistance as a result of her training, it had had no effect on her, but it would have numbed the sinews of an ordinary person, rendering them immobile.

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Fate/Strange Fake, Volume 2, Chapter 2