The sentence of this thread doesn't make any sense at all. Zelda is an established franchise with millions of fans all over the world, it's own fandom, it has had a tv show, movies, merchandise, and many many more, while Fable II, while it's an excellent game, it's just a recent RPG franchise, which the first game did very little to captive new gamers to it.
So no, i don't think fable 3 will be the zelda killer, just like there won't be a FF killer, a halo killer, and anything killer.
Games are good as they are, just because you prefer one before the other, doesn't mean that it "kills" it
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