I have come to the conclusion that based on the subtle evidences presented in Ch. 626 that Madara used a genjutsu or possibly a form of limited Tsukuyomi to make Hashirama think he killed him.
Take a look at this:
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Don't you find it peculiar that Madara's EMS was activated after dislodging from Kurama?
And that the image of the Moon appeared Immediately after that panel:
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It's because Madara had already cast the genjutsu on Hashirama just before they fought mano a mano.
And that is why Madara's EMS was already deactivated at the preceding panels, the genjutsu has already been cast:
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And after Hashirama "killed" him, this was shown:
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And did you notice Hashirama's peculiar upward glare:
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And did you notice the peculiar "diamond shape" symbol?
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That is the manga/anime trope for optical illusion/mesmerization
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And that is why the same image/symbol appeared on the moon and on the panel after Hashirama looked upward:
Before the fight:
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After the fight:
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The genjutsu had just ended/ wore off that is why Hashirama fell to his feet:
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That is why Hashirama has no idea how Madara survived even though he was apparently sure he killed him:
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Because Hashirama was under a genjutsu at that time. Hashirama might have injured Madara but Madara was not killed because he used a genjutsu or a limited form of Tsukuyomi during that fight:
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Using the Moon:
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