In Remi Card,we know that 4 symbols different between the others..but as i know that this 4 kings of this cards is a symbols of 4 kings that knowed as the greatest at their era :

Spades - King David

Clover - Alexander The Great

Heart - Charlemagne

Diamond - Julius Caesar

But this story is still half to half for their truth....because still  so many mystery that can't be answer untill now,like why jack's card called jack?why not prince or duke?why jack just have one eye?and why jack of heart doesn't has mustache??well history always have their mystery :D

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