That's not quite correct. For instance, Avenger was summoned by the Einzberns, in place of a Berserker class Servant. So, there still were only seven Servant classes during the Third War, not eight. There was an eighth Servant, but it was a duplicated Saber, thanks to a completely different group cheating, and had nothing to do with the presence of Avenger. Additionally, Zouken and the Einzbern head were Masters in the First War, IIRC.
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Stand between the Silver Crystal and the Golden Sea.
"Youngsters these days just have no appreciation for the magnificence of the legendary cucumber." --Krityan Elder, Tales of Vesperia.
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Stand between the Silver Crystal and the Golden Sea.
"Youngsters these days just have no appreciation for the magnificence of the legendary cucumber." --Krityan Elder, Tales of Vesperia.