Nasu: As a side note, Kojiro even fended off Berserker once. There is a Japanese proverb that says you can fend of any enemy if you have the right skills. Even if you can't claim victory, you can at least chase them away. Kojirou's style of defense is more of an offensive-defensive style, where instead of protecting himself from his opponent's strikes, he takes the stance of, "If you come any closer, I'll probably die but I most certainly will take you with me". If Berserker had gone for the kill against Kojiro, Berserker would have been decapitated the moment his weapon reached Kojiro. Of course, Berserker has God Hand: Twelve Labors, so if he really had gone for the kill, that would have simply been the end of Kojiro. But Illya knew Assassin had Caster behind him, so she chose to avoid charging in recklessly with Berserker.

Fate/complete material II; Characters: Assassin, pg. 88-89