Luffy took damage only from Kaido, while Kaido took damage from 15 OTHERS, and they weren't some random fodders, they were the main force of the alliance.
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Kaido didn't take any tea/lunch break.
Couldn't help more.
Luffy got knocked out by Apoo. First thing he did on raid was getting knocked out by Kaido's subordinate.
Luffy clashed with Ulti and had to be saved by Yamato.
He already used G4 like 4 times(nave battle + number + rooftop + comeback to rooftop) and still has the drawback.
Already got knocked out 2 times by Kaido.
Luffy has only bullshit plot armor on his side. And fanboy saying he is 100% just because he ate something.
Kaido fought 15 people many of them fodders comparate to them. Kid literally did no damage to him and I could argue that Law also since he only attack that should make some damage(internally) may have hit an empty spot.
Kaido's true damage were just Luffy ACoA and ACoC attacks + Zoro Ashura. The rest are irrelevant or minimal damage.