The world of One Piece is a peculiar one that has perplexed readers for ages. One of the oldest mysteries of the series has been the reason why its world is covered in oceans and dotted with islands. Needless to say, it's a world very different from our own, with topography unique beyond imagination, and logic that makes one question whether it is even governed by the same rules as our own.

That said, Imu's use of a particular cataclysmic weapon in chapter #1060 could hold the answer to the age-old mystery and also explain the existence of the hole at Enies Lobby, among several other mysteries.

The destruction of Lulusia in chapter #1060 had catastrophic consequences across the globe, including earthquakes, tsunamis, and most importantly, a rise in sea levels across the world. Chapter #1089 further states that sea levels rose by one meter across the four seas, flooding several islands and forcing many to evacuate. If Imu is truly one of the first twenty rulers that formed the World Government, as hinted by Cobra in chapter #1085, then the weapon used to eradicate Lulusia could very well be an Ancient Weapon. Considering the sheer destructive force of the weapon, One Piece's world could very well be the result of heavy use of similar weapons during the Void Century which caused sea levels to rise exponentially.

The Sea Levels in One Piece Could Be a Byproduct of Warfare

This rise in sea levels would have led to many islands, like Water 7, sinking over time or being submerged completely like the old Wano Country. The massive robot found on Egghead Island further proves such technologically advanced weaponry could have easily existed during the Void Century with fuel alternatives much more efficient than the Mother Flame used by Imu in this case. The use of such weaponry could also explain the existence of the hole in the ocean at Enies Lobby. The hole created where Lulusia once was bears a striking resemblance to the one at Enies Lobby with both appearing to be massive circular waterfalls. While it is unclear where exactly the water at the bottom of these waterfalls goes, one plausible explanation is that the hole is actually a void, and all the water that was once there has been displaced – hence the rising sea levels.

This could also explain why Water 7 is constantly sinking seeing as it is located not far from Enies Lobby. Notably, chapter #1089 of One Piece shows the consequences of Lulusia's destruction 29 chapters after this happened in the manga. It seems odd that Eiichiro Oda would return to an event of the recent past, especially in the middle of One Piece's hectic final arc. Mentioning that the sea levels have risen by one meter may seem an inconsequential detail, but it's actually a pretty catastrophic event, and the manga rightfully underscores it by saying that entire islands have been evacuated.

Enies Lobby Could Have Been Created During the Void Century Using an Ancient Weapon

The hole at Enies Lobby was most probably created during the Void Century using the same weapon used on Lulusia. Repeated uses of this weapon during that massive conflict may have caused the sea levels to rise so much that most of the landmass of the world has been submerged, leaving only the Red Line - which has been described as the place where the "gods" lived, and thus was likely at one of the highest altitudes in the world. This would also explain why the Celestial Dragons ousted and hunted the previous inhabitants of the Red Line, the Lunarians. It would certainly be a shocking surprise for fans if the world of One Piece looks the way it does because Imu and the World Government have used a devastating weapon in the past, literally shaping the world to their whims.

One Piece is available from Viz Media.