that barely did anything.
by significant damage, i mean luffy's adv CoC punches and zoro's ashura. that's all. everything else that the supernova threw at kaido barely did anything.
Kaido has some sorta weakness to fire imbued with haki.. like red rock and red hawk..
bruh what? firstly red roc and red hawk did barely as much damage as the g4 barrage luffy emptied on dragon kaido. and even in those, the trick is the advanced armament not the flames.
Wanji serious flames can hurt kaido moderately if not intensely (ofc this is an assumption seeing how he hasn't gone all out and now hasn't even intensified his flame against 2 Yc.. make me curious)
Marco can definitely hurt kaido and make him bleed seeing how his powers work.. i hope we can agree on this
and if sanji damages queen with intense flames or a move that burns right through queen... then like marco sanji can hurt and make kaido bleed seeing how Marco could bypass queen's defenses..
when was it ever said that kaido is weak to flames?
all he's weak to is adv CoC. any attack which doesnt have advanced CoC is barely scratching him. attacks with adv CoA are slightly hurting him but nothing significant. he heals past those easily. im sorry but all of this flame stuff sounds like a nonsensical headcanon tbh.