Not being disrespectful to zoro but.., did he even have a slightest idea about how powerful a yonkou is..?, I mean he already set himself up there, a battle between him and a yonkou
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. No clue, no nothing, never even met one before..
While luffy still carelessly optimistic at least he already had the glimpse since he already fought 2 before.., but zoro..?, c'mon man..