One Piece's Wano arc could have potentially foreshadowed how Dr. Vegapunk's survival could take place by having him come to Elbaf in the shape of Eustass Kid. There has been a running theory in recent days, stating that the Vegapunk Satellites are centered around the Seven Deadly Sins, and the seventh one could be Kid, based on what was shown during a panel in the Wano arc.
Furthermore, this moment in One Piece's Wano arc could also cement some elements of Kid's character and all of that could come to fruition during the events of the Elbaf arc, thus nullifying Vegapunk's death at the hands of Kizaru in the current Egghead storyline, although that hasn't been fully confirmed in the manga at the moment.
However, this would be a very interesting twist and one that could add layers to both Kid and Vegapunk's characters.
Disclaimer: This article contains spoilers for the One Piece series. Any opinion expressed here belongs to the author.
Explaining how One Piece's Wano arc could not only explain Vegapunk's survival in Elbaf but also connect it to Eustass Kid
This theory suggests that Eustass Kid is connected to Dr. Vegapunk and that he is the seventh of the Satellites since the latter are meant to represent the Seven Deadly Sins. As of right now, the manga has shown six of Vegapunk's Satellites, featuring numbers 1 to 6, and One Piece's Wano arc showed Kid using his attack Damned Punk, with his metallic arm having the number 7, thus adding to the theory in question.
There is also the element that all of Kid's attacks have Punk in the name, as shown in One Piece's Wano arc, although it is fair to say that could be based on him having a sort of Punk Rock aesthetic in his design.
However, the theory goes further and explains that perhaps Kid was one of Vegapunk's Satellites who got lost a few years ago, lost his memory, and started to make his own journey as a pirate, displaying a lot of pride and arrogance, which is the missing Sin among Vegapunk's offshoots.
Another element that cements this theory based on One Piece's Wano arc is the fact that Kid, as a child, was capable of creating mechanical objects in a matter of seconds without much problem, which could be a direct result of having the doctor's brain and his genius. And considering where he landed after his battle with Shanks, there could be a chance that Kid survived and is in Elbaf waiting for a reunion with his creator, thus possibly confirming Vegapunk's survival in Egghead.
Debating whether Vegapunk should die or not

While this theory involving Kid and what was shown in One Piece's Wano arc could lead to interesting developments for the former, it would actually be a disservice to Dr. Vegapunk if he manages to survive the Egghead arc. This is due to the fact that the series has a running problem of a lack of major casualties in high-stakes situations, with Whitebeard and Ace in Marineford being the only exceptions.
Even One Piece's Wano arc, which was a major turning point for the story, doesn't have any significant deaths, with the characters of Kaido and Big Mom still not confirmed to be alive or dead. Therefore, Kizaru killing Vegapunk could add much-needed tension and stakes at a time when it feels that the Straw Hats rarely lose and their members are not going to be taken out.
Final thoughts
This new theory suggests that Eustass Kid's metallic arm with the number 7, shown during the events of One Piece's Wano arc, could mean that he is the seventh Vegapunk Satellite. However, there is not enough information at the moment to confirm that is true.
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