One Pice Has been around for a while, and that's left room for speculation. These are some of the most popular One Piece fan theories that hopefully will one day be proven true.

Eiichiro Oda’s One Piece is one of the greatest and longest-running fictional series of all time. After 22 years, Oda confirmed that only 80 per cent of the series has been completed so far. During that time, fans have developed plenty of theories regarding the series' plot and its characters.

Some are more recent, while others have been left unresolved as far back as the series' debut in 1997. With the Wano Country arc, the most anticipated arc in the entire series, being nearly half-way through, more interesting theories are on the rise and we certainly hope that eventually come true. The following list features 15 ongoing One Piece theories that fans hope will inevitably come true. Fair warning, this list may delve into some spoiler territory, so proceed with caution.Updated on: December 21, 2019, with some of the most interesting Wano theories that we can't help but wonder about!

15 Shanks is the Father of Makino’s Baby

On the cover story of chapter 614, Makino, a close friend of Monkey D. Luffy from his hometown, is seen holding an infant while smiling at the news of Luffy’s return. In SBS volume 63, Oda confirms that the child is Makino’s. He also teases that the father is "probably that person”. There are plenty of fans who believe that the father is none other than Red-Haired Shanks. After all, Shanks and Makino have known each other for years and have a positive relationship. Not to mention that there was plenty of time for Shanks to visit the East Blue during the two-year time skip. Therefore, the likelihood that they conceived a child together is pretty high.

14 Monkey D. Dragon Is A Wind Man

Monkey D. Dragon is one of the most mysterious characters in One Piece. Even after two decades, very little is known about him. The only thing that fans are certain of is that he likely possesses Devil Fruit powers. Based on evidence from the Loguetown and Post-War arcs, Dragon demonstrates that he has the power to control the wind and air currents. As a result, this would make Dragon a wind man and possibly a logia-type Devil Fruit user. With the power to control an element as versatile as wind, it is no wonder that Dragon is considered one of the most dangerous characters in the series.

13  The Giant Strawhat Is Connected To Uranus

One Piece fans experienced quite a shock in chapter 906 following the revelation that a giant straw hat similar to Luffy’s is located in a frozen chamber under Mary Geoise. While not much is known about it, it appears shortly after Donquixote Doflamingo talks about Mary Geoise’s national treasure. During the Dressrosa arc, Doflamingo mentions that the treasure could shake the world to its core. With such implications, fans have theorized the national treasure is the Ancient Weapon Uranus and that the straw hat is somehow connected to it. Some fans theorize that the straw hat contains a secret message on how to locate Uranus, others say that it is Uranus and some even think that Uranus is hidden under it.

12 Big Mom Made Kaido Unkillable

In chapter 907, Big Mom and Kaido argue about who gets to eliminate Luffy for interfering in their respective affairs. During their conversation, Big Mom mentions that Kaido owes her a life debt. Several theories soon developed to determine what kind of debt a Yonko like Kaido could owe to someone as powerful as Big Mom.

One theory suggests that his inability to die is somehow linked to her power to control souls. Considering that they were part of the mysterious group Rocks over 40 years ago, it's possible that she could have inserted souls into him to save his life or make him stronger.

11 Luffy’s New Gear Fourth Transformations

In the current manga arc, the Strawhats and their allies are preparing for their showdown with Kaido. In preparation for his rematch against Kaido, some fans predict that Luffy will develop two new Gear Fourth transformations. The first possible transformation could be one that specializes in aerial combat like “Eagleman”. The other is a "Tigerman" form that could possess enough striking power to break through Kaido’s scales. In Japanese mythology, tigers and dragons are often portrayed as equals, and Oda has made it a habit of frequently using mythological references throughout the series. Thus, "Tigerman" sounds like a definite possibility.

10  Blackbeard Is Three People In One Body

During the Marineford Arc, Blackbeard turned the world on its head by using two different Devil Fruit powers. A feat that was supposed to be impossible. One popular fan theory suggests that Blackbeard pulled this off because he has a condition known as "fetus in fetu" and that he has two siblings inside him.RELATED: Jump Force: The 10 Most Powerful Fighters, RankedEvidence supporting this theory include how Luffy and Zoro mention during the Jaya arc that Blackbeard is possibly "more than one” guy. During the Marineford arc, Marco also mentions that Blackbeard's body is unique. Finally, his Jolly Roger has three skulls. A design that is similar to a two-headed Jolly Roger belonging to the pirate twins the Decalvan Brothers. All this points to Blackbeard being a genetic chimera.

9 The Ancient Kingdom And Raftel Are The Same

Before their deaths, the scholars of Ohara managed to identify the true name of the Ancient Kingdom. Unfortunately, the Gorosei made sure the name would remain a mystery by destroying them. After the Straw Hats meet Rayleigh, he explains that Gol D. Roger and his crew not only reached Raftel but also uncovered the secret of the Void Century and by extension the Ancient Kingdom. Furthermore, Whitebeard reveals in his final moments that the discovery of the One Piece will turn the world "upside-down". These facts help to support the theory that the island of Raftel and the Ancient Kingdom are one and the same.

8 Joyboy Was The Ruler Of The Ancient Kingdom

During the Fishman Island Arc, Robin discovers a Poneglyph inscribed with an apology from someone named Joyboy to a mermaid princess, who was also the Ancient Weapon Poseidon. A theory soon emerged that Joyboy was the ruler of the Ancient Kingdom. Evidence supporting this theory is based on how Joyboy shares several similarities to a Javanese king named Jayabaya, or Joyoboyo in Javanese.RELATED: The 10 Most Powerful Sword Art Online Characters, RankedJayabaya predicted the fall of his kingdom and had its history transcribed in books and epigraphs, much like how the Ancient Kingdom did with the Poneglyphs. He also prophesized that a chosen one called Ratu Adil would restore harmony to the world. This also reflects Luffy as the destined hero based on his connection with Shirahoshi, the current Poseidon.

7 Devil Fruits Are Linked To Electromagnetism

For years, countless fan theories were created to explain how Devil Fruits work. One theory developed by CAMUNAI explains that the properties of Devil Fruits are centered around electromagnetic waves. The theory uses the science behind electromagnetism to explain how Devil Fruits work, as well as their weaknesses to water, Sea-Prism Stone and Armament Haki. To summarize, water, composed of polar molecules, absorbs the electromagnetic waves of Devil Fruit users which weakens them. Likewise, Sea-Prism stone supposedly shares similar properties. It even manages to explain how Armament Haki affects Devil Fruit users thanks to a phenomenon known as “black body”, where a body or object absorbs electromagnetic radiation.

6 One Piece And The Inherited Will Theory

The "Inherited Will" theory by Ashura_KingFisher is one of the most popular One Piece fan theories. It explains that the One Piece is a project developed by the Ancient Kingdom that involves using the Ancient Weapons to destroy the Redline. Theoretically, this would unite the Grand Line, the Calm Belt, and all four Blues into one ocean. Furthermore, this would also create the legendary All Blue. In chapter 610, the mermaid Madam Shyarly has a vision predicting that Luffy would destroy Fish-Man Island. This also correlates with the theory because destroying the Redline would also destroy Fish-Man Island. However, this also means that its inhabitants would finally move to the surface. Effectively ushering a new era of coexistence between humans, fish-men and merfolk.

5 The Wano Traitor

With the Wano arc having well and truly begun, fans quickly found themselves back to discussing a very important theory. Who exactly is Wano's traitor? When Jack somehow found the Phantom Island Zou and knew that Raizo was there, people started raising their eyebrows because someone was, evidently, leaking information to the Beasts Pirates.

At Wano, somehow, Orochi and Kaido kept getting Intel on the alliance, and after analyzing every single candidate, Marco_OPT seems to think the traitor is none other than Kanjuro. He was at Zou, and he did little to no work at Wano. Furthermore, his past is shady as well. We certainly hope that this theory is true.

4 Shanks' Sword

Shanks is one of the current Yonko in One Piece whose powers we've been waiting to see. From the looks of it, he is primarily a swordsman as he is often seen carrying one. Recently, Oda revealed its name to be Gryphon.

In One Piece Chapter 965, we got our first proper look at the Roger Pirates, and the sword that Roger varied was eerily similar to the one that Shanks' currently has. Shanks had also inherited Roger's hat in the past, so it won't be a surprise if he held his sword as well. For now, this remains to be a theory, but we would love for it to be true.

3 Shimotsuki Zoro

Roronoa Zoro's past has been very much kept under the covers by Eiichiro Oda. Although we are told that he's from East Blue, there's also the fact that Oda clearly said that a vessel left Wano 50 years ago and arrived in East Blue. With Koushiro having the same symbol on his outfit as those seem in Hakumai, it is possible that he, along with Zoro, is from Wano Country.

Roronoa Zoro is speculated to be a member of the Shimotsuki Clan of Wano, one of the Daimyō families of Wano. Who exactly is his father, or what connection he bears to Yasu, or Ushimaru isn't known, but we'll likely find out soon enough.

2 Trafalgar Law's Death

Oda rarely ever introduces things and never follows up on them. During the Dressrosa arc, Oda revealed the secrets of the Ope Ope no Mi and told us how the Perennial Youth Surgery could grant immortality in exchange for the life of the user.

At Wano, many believe that Trafalgar Law will fall and end up using the Immortality surgery on someone. Law's death has been foreshadowed many times, and although he's a fan-favorite, having main characters die adds a good twist when there's a significant reason behind it.

1 Blackbeard Is From A Snow Country

In One Piece Chapter 966, The Whitebeard Pirates clashed against the Roger Pirates and it was revealed that their friendly battle lasted for 3 days and 3 nights. On the fourth day, when everyone was partying, Buggy and Shanks mention that Blackbeard hasn't slept at all. In fact, he's rumored to have never slept in his life.

Interestingly, during the Drum Island arc, Luffy mentions that someone, likely from Shanks' crew, told him once that people in a snow country don't sleep or they'll die. Since Blackbeard doesn't sleep, it could well mean that he's from a Snow Country, and maybe isn't human at all!

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