In this theory, I would like to go in a step by step manner so I will split in in parts.
First I will discuss the participants and their purpose. Then the foreshadowings of war. Then some predictions as to what may happen. Finally a speculated conclusion. Let’s begin.
PART 1:- PARTIES TO THE WAR
2) Supernova alliances
4) Outsiders (there’s a surprise awaiting here)
Obviously I will begin with the man who will begin the war. There’s not much to explain here if you read the chapter on Kaido(Chap 795). That was the biggest foreshadowing. Let’s go into his other reasons apart from waging a war like it’s a college sport and he is the team captain.
In that same chapter, we saw him land right in front of the captains of a supernova alliance who were already looking to take down a yonko even though Kaido wasn’t the target. There are 2 possibilities here:-
I) Either they are all smashed to bits which i don’t think is likely at all.
II) Kaido planned to start a war and they agreed to fight then rather than now and the alliance was spared. (This is what would have happened. Kaido wants a war and not a skirmish)
Another reason is “Law also notes that if they kill Doflamingo and destroy the factory, Kaido will transfer his grudge to the pirate alliance.”(wikia).
Though he probably didn’t hear it, if he realises it any later, it fits perfectly with his motive for a war.
The Third and last reason:- During the Marineford War, Kaido wanted to fight with Whitebeard but was intercepted by Shanks. For Shank’s behaviour, fighting is the last option plus if they fought, they definitely couldn’t make it to the war. Definitely Shanks must have talked Kaido out of it. But is it so easy talking out a man like him? Absolutely not. Kaido must have gotten some sort of promise from Shanks for a future fight or something or some other sort of diplomatic agreement. Perhaps Shanks will be invited now if Kaido wishes to start the war.
Those are for Kaido’s reasons.
B) Big Mam
She has quite some beef with the supernova alliances as well. Luffy’s challenge to her and Kid destroying her ships.
Also just recently they again saw the Straw Hats Sunny group holding Caesar hostage who is a target for Big Mam as well as the supernova who allied with her Capone Bege. Bege himself has a bone to pick with Luffy because of the admiral being summoned to Sabaody Archipelago because of you know what
Also the yonko’s are stubborn so I suppose she wouldn’t have forgiven Kid either and naturally she will want to participate in the war to show her wrath.
A schemer and a coward but a perfect opportunist. We already know he is on the hunt for Devil Fruits. Naturally the strongest Devil Fruit users will be Yonko captains or their commanders. Wouldn’t he be fantasising having Kaido’s devil fruit. However this means as usual he won’t enter the war until the end.
He will come just to steal the spoils i.e take devil fruit abilities and territories of any fallen Yonko crew.
I don’t think he will be part of the war from the beginning either. As a person who would keep fighting as a last resort, he may either enter the war half way through or in between to protect Luffy for the timebeing (I will explain this in predictions for the war) or to intercept and stop Blackbeard or he may later on be forced by Kaido to join the war somehow (as discussed earlier)
2) Supernova Alliances
A) Kid-Hawkins-Apoo alliance
They already wanted to take down Shanks but had Kaido land right in front of them. Do they have much of a choice? They anyway wanted to take down a yonko and Kid being the stubborn guy as he is, I don’t see why he wouldn’t want to participate in the war.
B) Luffy-Law alliance
A war where the yonkos are going to take part. Do you think Luffy can resist it? He already wants to take down all 4 of the yonko. Kaido was his first target but unbeknownst to Law, Luffy already mocked Big mam into a fight. Both his targets being at the war and with his excitement to do stuff where Nami,Usopp and Chopper will freak out of fear is barely containable. I guess you can already see his twinkling eyes. Anyway this would be an unavoidable scenario for them so it’s not like they have a choice.
Now why would Marines want to interfere in Yonko’s war and business? If you remember Jinbe explaining to Luffy that Akainu shifted Navy HQ in the New World, then there is only 1 reason why he would step in the turf of the Emperors i.e if he wants to make it his own turf. We already know that New World is ruled by Yonkos when Garp was explaining this to Luffy in Episode 313. This means that the World Government had minimal control there. Obviously you can’t expect to take down all 4 and rule supremely. They had a hard time beating 1. Akainu himself is also an opportunist and will slowly want to bring more New World territories under the Government’s control. This is the perfect opportunity where you have the Yonkos face off each other. They become easier targets for a cunning schemer like Akainu. He also will want the Marines move in at the last moment just to claim territories so that there is minimum damage to his forces and at the same time he manages to pull off some territories from the Yonkos into the Government hands. Hence the marines would be late interrupters.
Another reason is because they have to do damage control first after what happened in Dressrosa and reinstate their reputation as much as they can after its recent plummeting in nearby kingdoms. They can’t just jump in the war after such a blunder. So they will take part but a late entry rather than right from the beginning. Akainu will let them damage each other and then jump at the right opportunity.
4) Other participants
A) Gecko Moriah
We already know he hates Kaido because Kaido killed his crew. He definitely will look to join forces with some other war participants to take down Kaido.
He already entered the New World again and was hiding from Marines attempting to capture him.
I expect him to make an entry too. He won’t be idle sitting and doing nothing when the whole New World in engulfed in war.
He did state his ambitions of becoming a Yonko. Though he really won’t be serious when such big names are involved. He may look to be an opportunist and show his face at the war and still do almost nothing except ‘accidentally’ helping Luffy or Shanks a little
D) Whitebeard Pirates
They will also join the war at some point to help protect Luffy. We saw Marco say that Ace’s will lives on in Luffy and I feel they may enter the war to protect Luffy from Blackbeard and Akainu.
Now the big surprise.
E) Golden Lion Shiki
He is a canon character as mentioned by Magellan to be the first person to escape Impel Down. Though Strong World is a non-canon movie. Oda-sensei may have something planned for Shiki and it obviously won’t be something small. If we consider Chapter 0 of One Piece, he wanted World domination. However he failed to convince Roger and later on was captured (long story, will just pick relevant parts). He made the following statements too
He despises the New Age and also wants to rule and dominate the world. Yonkos, supernovas etc. was all created in this new era though it had some old timers like Whitebeard. When all the people of the New age gather for the war, this presents him the perfect opportunity to fulfill both his goals; i)Become a Yonko himself and claim territories under his rule & ii) Teach the New age supernova pirates and others a lesson as he stated in the above image. He isn’t an ordinary man and moves with huge fleets perfect for a large scale war and he is a powerhouse himself. Everything simply adds up.
PART 2:- FORESHADOWINGS OF THE WAR
The first foreshadowing :- Kaido
It makes everything obvious doesn’t it? He wants to start the greatest war and definitely the greatest war wouldn’t just be of small scale with 2 or 3 participants. Hence all the above participants.
Chapter 799-The parent child relationship. If these people were to just help Luffy during 1 war i.e the Final war, why would Oda rush things. We were expecting Luffy vs Fuji and ended up with something even more epic. LUFFY COMMANDING 5600 PEOPLE!!! Obviously there must be something coming. Still not convinced? Then here’s another evidence.
In this page Law explains it all why Luffy needed a fleet to pick a fight with any yonko. They needed a strategy and a big fleet. However with Doflamingo gone and Kaido wanting to start a war, the initial plan is tossed out. I feel Oda was building upto this silently. Law’s explanations after Punk Hazard Arc and the events at the end of Dressrosa Arc. Also the end of Fishman Island arc. At the end of every arc, Oda-sensei has given hints as to this which prompted me to wonder why and led me to making this theory. It’s like a chain if you observed.
Third is a speculation
A war before the timeskip. I personally expect a second timeskip. There is alot to uncover both plot wise and in character development. I almost feel like One Piece isn’t more than 60 percent complete yet. No one knows Zoro or Sanji’s real origins. We straight away saw their childhood and both have mysterious abilities. Luffy has alot of development to do both in strength and somewhat in character as well.
Finally it is unimaginable to have a 19 year old Pirate King. Wouldn’t that simply make Roger Rayleigh and everyone a joke?
Before the first timeskip we had an epic war which had a massive impact on everyone especially Luffy. Something similar would happen in this war which shall signal a timeskip where all straw hats train further before Luffy can finally become Pirate King and wage war with the Government itself to abolish all the crappy systems. The Void century and Will of D will be discovered after that. Hence there would be a war after which a timeskip.
PART 3:- SPECULATED EVENTS OF THE WAR
I would be a fool if I really tried to predict Oda-sensei as to the entire events of the war. I pretty much explained the reasons and foreshadowings because there was evidence. However what happens in the war is pure speculation.
However somethings where I can atleast discuss a possibility are as below:-
Revolutionaries will not take part again because if they were to, then more details about some of their strong commanders would have been hinted atleast. Sabo has yet to master the Mera Mera no Mi and apparently isn’t strong enough to take on one of the strongest Yonko commanders or Navy Admiral in a serious war yet.
That leaves Dragon. Ivankov is strong but not really a very high level powerhouse. There are some theories as to Aokiji being a revolutionary but as of now we can’t say anything. If Revolutionaries were to go to war, we would atleast know of some preparations and some of their strong powerhouse character introductions. That hasn’t happened.
The war is still far away as we haven’t yet seen any New World nakamas actually join. Luffy’s fleets are also in development especially Hajruddin and Ideo’s crew. We have yet to encounter Wano-kuni arc and whether we get to see Elbaf soon or not is also yet unknown. So the war will still take alot of time to begin.
In the war, I expect Big mam and Kaido to fall with Kaido being dead again killed by perhaps Blackbeard or Akainu. Luffy Law and other supernovas will have a hard time in the war and will barely survive the war. They will do damage but won’t exactly be victorious. Luffy and Law had such a hard time against Doffy so how can we expect them to take on Kaido of whom Doffy was scared as shit! Blackbeard will steal some devil fruit abilities for his crew while Akainu will conquer some territories for the World Government. Shiki will rise to power as a new Yonko.
Big Mam and Luffy will fight which will be stopped midway by Nami realising Big Mam is Lola’s mother from the vivre card and will use that to stop a fight to the death and rather end the bitterness from going to worse. Big mam will be alive but will lose her status as Yonko.
Luffy will manage to claim some unruled territoties and fishman island as his own. By standing upto Big mam and probably fighting well, he will manage to convince her into giving up Fishman Island to him while claiming territories like Dressrosa,Prodence,Wano Kingdom and Kano Kingdom and maybe Elbaf as his own territories which will be protected by his fleets when he enters the Time skip.
There will be some deaths but who exactly we do not know. People predict Shanks to die but whether he dies here or not I cannot say. The war will end with an imbalance again. Lack of 7 shichibukai, and perhaps only 3 yonko.
Why i feel Luffy won’t be a yonko is because he wants to be Pirate King. He wants to defeat all 4 Yonkos and find One Piece rather than usurping their positions. How can he enter a timeskip if he is yonko? Can you imagine a Yonko whose whereabouts go unknown for 4-5 years?
When Luffy becomes Pirate King, there will be no yonko system and there will be 1 sole ruler of the sea with utmost freedom.
Also people predict X Drake to join Luffy and Law alliance by betraying Kaido. I want it to happen but whether it happens or not, I cannot say. He does have some unspoken history with Law.
Also I expect the Whitebeard Pirates to show up and help Luffy against Blackbeard and Akainu to survive.
That is more possible as they will show up sooner or later and Marco spoke of Luffy carrying Ace’s will.
1) Imbalance in Shichibukai due to pre war and war activities
2) Kaido’s death and Blackbeard stealing his devil fruit and many others.
3) Big mam’s fall from power and Akainu establishing World Government control over previously Yonko territories.
4) Shiki’s rise to power and claiming of terrotories,
5) Straw Hat Crew and alliance survival and signaling of a time skip.
6) Kid, Buggy and others also claiming some territories.
7) No ultimate powers in the New World as many people have some territories among them.
Government, Shiki, Blackbeard, Shanks (if alive) having big territories while Luffy and others claim few small territories as their own.
[Have a nightmare that Shanks may die while protecting Luffy trigerring another catalyst for Luffy like Ace.] 8) Changes in marines and more connections being established (like Drake joining Luffy Law alliance perhaps)
9) Showing up of Whitebeard Pirates again
Summarising all of the above, alteration in the structure of New World and a Time Skip.
*Theory by Portgas D. Shanks