Kaido and Big Mom have been two incredibly tough opponents for Luffy and the Straw Hat Pirates over the years, proving to be super-powerful with numerous unique abilities and deadly Devil Fruit powers to match. While these characters have shown animosity towards each other in the past, the sudden and mysterious change in their relationship has left many One Piece fans wondering why Big Mom and Kaido have formed an alliance.

Big Mom and Kaido have formed a temporary alliance for the success of the New Onigashima Project, which involves finding and using the infamous ancient weapons to spark war in the One Piece world. They also aim to claim the One Piece treasure in the process and have offered to become enemies again once the plan is complete.

While it may be understandable that Big Mom and Kaido would form an alliance given their shared goals and common enemies, it was certainly an unexpected turn of events—and many One Piece fans are now curious to know what their true goals might mean for the main character. One Piece characters. Stick around to find out everything there is to know about Big Mom and Kaido's history, their goals, as well as why they actually formed an alliance in One Piece.

Big Mom and Kaido's Relationship and History (Rocks Pirates)

The Rock Pirates are arguably the most powerful and infamous pirate crew in the history of the One Piece world, though the crew is disbanded during the story's run. Very little is known about the Rock Pirates as a whole, but fans do get a glimpse of the members of the Rock Pirates crew—two of whom were actually younger versions of Big Mom and Kaido.

Alongside other iconic One Piece pirates like Whitebeard and Gol D. Roger, Big Mom and Kaido have managed to rack up insane bounties in One Piece—a figure often used to estimate a character's overall power level. Big Mom's bounty is set at 4,388,000,000 berries, while Kaido's bounty is listed at 4,611,100,000 berries—which would give them the highest One Piece bounty of all time when combined.

It has been said that the Rock Pirates include some of the most powerful pirates in One Piece, including the most powerful pirates ever explored in the Grand Line. Big Mom and Kaido certainly don't get along very well, but it's very clear that their long history and background make them capable of working together with incredible compatibility and effectiveness—the Rock Pirates were founded with a powerful crew, after all.

Why did Big Mom and Kaido form an alliance in One Piece?

As One Piece's Wano arc approached, fans were in for a huge, plot-altering surprise: Big Mom and Kaido were actually forming an alliance in the official sense. They even went so far as to announce their new alliance to the others, seen below, thanks to this video posted by Crunchyroll Collection.

Although they appear very cheerful and friendly towards each other, Big Mom and Kaido have made it clear that they still wish to defeat each other—and that this alliance is merely a temporary means to an end, unlike what one would expect from a typical alliance. But this raises even more questions since there must be a very specific reason why such an alliance was created between the two.

Given the history of these two iconic One Piece villains, being part of the most feared pirate crew in history, in addition to each of their respective crimes and dark powers, there is real cause for concern among One Piece characters and passionate fans. Many now fear that, while the Rock Pirates remain a distant memory, the wrath of the Rock Pirates could return with Big Mom and Kaido's new collaboration.

Big Mom and Kaido's Goals (New Onigashima Project)

Kaido had been teasing for some time that he had a very special and crucial announcement to make, particularly regarding the future of the Wano region. He dubbed this announcement the "New Onigashima Project" and indicated that an alliance with Big Mom and her crew by proxy would be necessary for the project to succeed.

In One Piece manga chapter 985, Kaido detailed the plan for the new Onigashima Project and its true intentions, revealing that it would certainly be great for these iconic antagonists—but incredibly disastrous for the people of the Wano region. But he also revealed that another key objective of this plan was to recover the One Piece treasure, provided the previous stages of the project went accordingly—which could be the main motive for forming an alliance with Big Mom.

He also goes on to state that the Seven Warlords of the Sea were disbanded by the One Piece Navy because they have a more powerful force to take on the Emporers. This was another reason why Kaido believed he needed to form a single unit or team, as he would need a crew strong enough to locate and harness the mysterious ancient weapons in the One Piece world—the source of many wild One Piece theories.

Forming an alliance with Big Mom and her crew was just one step closer to wielding the power of the Ancient Weapons, which they would use to plunge the world of One Piece into an era of catastrophe and war—using all remaining civilians and survivors to man weapons factories throughout the Wano region. The two villains would use their newfound power and dominance to transform the world into a pirate paradise, in addition to claiming One Piece's treasure and power.

Can Big Mom and Kaido be defeated?

The prospect of what Big Mom and Kaido could do as a team is nothing short of terrifying, and taking them down could be far more difficult than expected. Starting with Chapter 955, fans began speculating on various ways Luffy and the crew could take on these two One Piece Yonkos, detailed below, thanks to this video posted by The One StrawHat.

However, things took a turn in Chapter 1050, when the volcano Big Mom and Kaido originally landed on erupted, likely forcing them to flee the Wano region before they could continue with their plan. Many fans at least believed Big Mom was dead, and possibly Kaido as well, though most fans believe it will take much more to bring them down after everything they've accomplished.

Additionally, Big Mom and Kaido's silhouettes were shown for a while, and they looked pretty good, not to mention that the Big Mom Pirates were hovering around the area and could have served as an escape route. So there's a good chance these two are still behind the scenes, plotting their next move.

Big Mom and Kaido have really put the main protagonists of this anime through their paces, and the thought of what they could accomplish together is cause for concern. Hopefully, these two can still be restrained and defeated (or at least restrained) before they do anything too wicked in the One Piece universe.

Were Kaido and Big Mom in love?

Since we're talking about Big Mom and Kaido together in the same sentence, we'd also like to address the question of whether the two were a couple in One Piece, meaning whether they were lovers or not, which is a topic often discussed among fans of the series as a whole. So, what's the rundown here?

Well, we know that Big Mom and Kaido were close, and the article analyzed their alliance and how and why they became so close, that is, what common goals they were bound by. But the situation may not be so clear to everyone.

Namely, we saw many scenes showing Big Mom and Kaido being very close, almost intimately close. They were seen drinking together, and during those moments, they looked like an old married couple; even their arguments gave off such an atmosphere, which makes perfect sense, given that old married couples often fight over silly things despite the love and respect they share for each other.

On top of that, many fan theories on Reddit and elsewhere stipulate that Big Mom and Kaido were actually a couple; in fact, we've already discussed a theory that states that Alvida, Luffy's first enemy in the series, could be a secret daughter of Kaido and Big Mom, which is based on the theories that claim the two were a secret couple. So, what's the truth here? Were they in love with each other or not?

For anyone who loves a good (fan) conspiracy theory, we have to disappoint you, as there's no real indication that Big Mom and Kaido were ever a couple or had romantic feelings for each other.

They were close, but both were pretty chaotic, and from our perspective, a relationship between them just wouldn't work. Also, Oda never hinted at a possible relationship between the two of them in canon, so there isn't much we can add here.

Ultimately, we can conclude that Big Mom and Kaido were close allies who managed to bond over certain common goals, but there was never any romance between them, and they were not a couple, nor did they have a secret child, as far as canon is concerned.