Originally Posted by
Nerd-o-rama
It only really applies to one route of F/SN. Rider was the midboss in Fate and I don't remember who it is in Heaven's Feel, but it's definitely not Caster.
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Actually looking it up, I guess the midpoint is Saber Alter ****ing up Shirou. Naturally the good guys lose in the middle of that route.
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If you stretch the definitions, you could say Black Berserker is the mid boss. Or Zouken, who's "offed" by Kotomine. Or then the Shadow who...mostly offs everybody trying to trouble her, but "dies" in the sense that after the forest she doesn't actually really appear anymore. Or maybe True Assassin, who Shirou actually gets to kinda fight and Kotomine gets to beat? I mean, the route is mostly the "good" guys (considering how Shirou acts with regards to Sakura, I'm not sure "good" is a very accurate description) getting their asses handed to them over and over until they win some pyrrhic victories towards the end. Everybody still gets more or less ****ed in most routes; in true Nasuverse tradition, the hero becomes the killer in the end.