I'm the Man that believe Zoro-san gonna cut Kaido head off.
But Oda-san won't make Zoro-san surpassing Kozuki Oden level because that gonna be only one person, and that person is Monkey D Luffy.
Oda-san won't make thing clear between Luffy and Zoro so it can continue debated.
It kind of complicated but knowing Oda-san writing, it sound 'One Piece' to me.
Zoro-san gonna cut Kaido head only in one condition.
'Kaido Weakest Stage Ever'.
My prediction at the the end of War if there no inference Big Name suddenly came out and stole the spotlight of SH and SN or possibly BigMom betrayal.
..After fighting Luffy-san and the other..
Momo appears turn into Dragon and shocked Kaido. After that either Momo gonna attack him or just talked to him.
Yama-guy also appears and said something that's gonna hurt Kaido feelings.
Kaido-san got angered emotional and at that time Kid-san fight him, launched his ultimate attack on Kaido.
Having a insane durability, Kaido attacked Kid but Luffy-san stopped him, and fight him continusly until he launched his strongest attacked.
Luffy-san beat Kaido.
Kaido fall...
Kaido-san remembering about Kozuki Oden, then Momonosuke and his little brat, Yama-guy.
Right at that time Zoro-san appears with his Enma, his Demon Aura, an Aura that we have not seen before
And Kaido-san said
'......Oden no it's can't be....'
splitblizting...
'Demon.....' sunachhi!!!
Kaido head cut off... (This gonna be happen in the most dramatic ever.... I can't find my word lol)
Everyone was looking...
All the beast pirates that still barely alive shocked and silence....
This his how i predicted the ending of War before StrawHat continue their next journey...