Ocean Pressure

Ocean Pressure is a phenomenon that appears on the edge of the Red Line. As explained by Marlin D. Swift, the Ocean Pressure is caused by upper level currents hitting, then sinking quickly against the Red Line forming an immense pressure pocket at the bottom of the Red Line before returning to the ocean.

He also explains that it is because of this, resin is needed to cross the Red Line unless you wish to be crushed to death. He also says that larger creatures are only shrunk by it's effects, as he explains this happened to him over fifty years ago.

Marlin D. Swift also explains that resin gains power from this, as the resin gains power when under pressure unlike most substances which are almost always crushed. Although, it has been seen that large fish and fishmen swimming freely through it because their skeleton is used to and adapted to the pressure, thus making them immune to the shrinking affects. The only other recorded effect change is during a story Marlin told Swift, in which a pirate crew of Giants went through and came to Fishman Island as midgets.

Trivia
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