It's safe to say that 2022 has been the year of One Piece. Not only has the "Wano" arc finally come to end after years, but Gear 5 was revealed, and the anime has even managed to consistently outdo itself in quality -- something long thought impossible by many. A new movie was even released this year, one specifically centered around the series' most mysterious character, Shanks.
With all this going on, it's easy to forget some smaller moments leading up to the present. For a long while, Dr. Vegapunk's secret project was teased as the weapon that would make the Warlord System completely obsolete. This is referring to the Seraphim, as manga readers are likely already familiar with. What they may not know is that according to one theory, the Seraphim might tie into one of the biggest and most important dangling plot threads in the series: the prophecy of the destruction of Fishman Island.
What did the prophecy say?
During the Fishman Island arc, a lot of confusion and chaos ensued after Madame Shyarly received a vision from her crystal ball that a man in a straw hat will destroy the island. Obviously, as Luffy is the most likely suspect based purely on appearance, she and everyone else assumed that he must be the culprit that commits the act. For the rest of the arc, Luffy was forced to find a way to prove his innocence to everyone on Fishman Island, managing to stop a coup d'etat in the process. This arc became important for a multitude of reasons, as not only was it the first to happen after the time skip and feature an island long teased in the story, but it also featured the first confrontation between Luffy and Big Mom, even if only over the phone. It also featured the first appearance of one of Luffy's most iconic moves, Red Hawk.
However, one thing that might be forgotten is that even after saving the island and earning everyone's respect, the prophecy was never outright disproved. If anything, the series made sure to imply, even after Luffy risked everything to save everyone, that the prophecy would still come true. In fact, while the vision originally only showed a silhouette of a man in a straw hat in the manga, the anime made it clear that Luffy was the one who would destroy the island. This is further supported through the story by Madam Shyarly's visions having a 100% guarantee of happening, with the only downside being that she can't predict exactly when they will happen. This implies that while Luffy saved Fishman Island at that moment, he might come back later to destroy it.
How Do the Seraphim Tie into This Prophecy ?
Somehow, in the same year that Luffy beat Kaido while using Gear 5, implied to be the same power as Joyboy, something even bigger might have happened. The reveal of the Seraphim is arguably one of the biggest plot twists the series has ever had, adding whole new elements to a franchise that's supposed to be setting up its conclusion. While very little is known about them, according to one theory, they might be the key to understanding the prophecy of Fishman Island's destruction.
Firstly, the Seraphim seem to be child clones of the Warlords, granted the powers of both Pacifistas and Lunarians. As such, they have become one of the strongest forces in One Piece, easily taking on both the Blackbeard and Kuja Pirates, seemingly with little effort. While the full extent of their powers is still unknown, it is clear that they are a force to be reckoned with.
According to this new theory, Luffy isn't the true culprit of Fishman Island's destruction, but rather, a Seraphim version of him is. As strange as that may sound, there is evidence to support the claim. First, if the anime didn't make a mistake, whoever destroys the island must either be Luffy or look exactly like him. So far, the only person that fits this description would be Luffy himself. That being said, it wouldn't be impossible for Seraphim Luffy to pop up at some point. While he was never a Warlord, the World Government forces have frequently been present during Luffy's adventure's on islands, meaning there have been multiple opportunities to grab a sample of his DNA, assuming that's a necessary step in creating a Seraphim.
Another aspect of the prophecy that supports this theory is the flames that are present in the vision. For whatever reason, the destruction of Fishman Island seems to involve a lot of fire and flames, which is rather strange considering this is an island that exists at the bottom of the sea. The idea that Luffy or anyone could set an underwater city on fire is rather hard to believe, but not if he had the power of a Lunarian. Granted, Luffy does have attacks that incorporate flames, such as his Red Hawk and Red Roc techniques, but they have rarely, if ever, shown the capability of generating that much fire. However, Lunarians seem to have the ability to generate and manipulate fire in a way that has only ever been matched by eaters of the Mera Mera no Mi.
Probably the biggest piece of proof supporting this theory is that Luffy doesn't seem to have any reason or desire to destroy Fishman Island. Not only did he risk his life to protect it, but he has friends who live there, making it even more unlikely. Luffy doesn't destroy things without reason, but considering that Luffy declared that Fishman Island would be under his protection, this makes it even more unlikely.
While Luffy has no reason to do this though, the World Government has many. Fishman Island has frequently caused them issues, whether it's due to the citizens fighting to be treated like equals or Fisher Tiger's assault on Mariejois. It wouldn't be too surprising if, during the World Government's efforts on eliminating threats to their rule, they decided to also rid themselves of a frequent thorn in their side that supports one of their greatest enemies.
For all the evidence that supports this theory, there is still no confirmation of any kind that it's actually true. The Seraphim have only just been revealed, and even then, they haven't really been explained. Most of what's known about them is based on hints and implications in the story, along with conjecture and theories from fans. In fact, while the only Seraphim to appear have been based on old Warlords, it's in no way confirmed that they are limited to only them, though the opposite also isn't out of the question. Only time will tell how the prophecy will play out, but according to the series, it definitely will. If this YouTube theorist is lucky, he might have actually cracked one of the series' biggest ongoing mysteries.