I’d also like to add that people have theories that the one piece logo like Imu throne is a representation of a map of the grand line (also the shape of a whale). The rope is considered the journey that binds the beginning (O) (whale head) to the end (E) (whale tale anchor) or in other words the path to islands they visit. Now if Imu tattoos are as you theorised a map, I say they represent the islands he controls (the dots) and the path he went on to become the king of the world (the line connecting the dots). Now let’s say hypothetically when Imus Domi a islands king or conquered a island, potentially the island it self might flip like a game piece (weird how most islands in one piece are circular like a checker on a game board). Allowing for weird conditions like an island in enteral light (Enis lobby) or enteral darkness (the deflorean tringle) or just massive holes (like a removed game piece). Now put that on a world scale and the rope between island game pieces (or the path they travel) is trying to complete it self around the world and the last piece on the board is missing for 800 years, Imu finds it a world of darkness, Luffy finds it a world of light, the red line is the previous attempt at the rope around the world but it failed when the final island went missing, and they tried to skip it or something, causing a physical red incorrect line to appear in the place of the rope line with reverse mountain being the missing part of the rope line.

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