Water Devil Fruit. The water devil fruit user would probably not die if thrown in water but heshe will not be able to move and needs rescuing to survive. Water devil Fruit- Mizo Mizo no Mi.
WaterdevilfruitWater Devil fruit THREE TypesThere have been many theories about the Water Devil Fruit so now I give to you my theoryThe single element o. The water devil fruit user would probably not die if thrown in water but heshe will not be able to move and needs rescuing to survive. If heshe can manipulate water heshe can easily split the seas or remove water from the water body thereby nullifying the side effect of eating a devil fruit Unable to swim.
Devil fruits are fruits that when eaten will give the user an ability that can fall under any of the three categories.
Therefore an aquatic Zoan which will have gills will have the ability to take in. Some might argue that Conquerors Haki is really rare and OP but If you think about it its rear but its not that al. In my oppinion it wouldnt be impossible for a water devil fruit to exist. While inferior to the Goro Goro no Mi this fruit is among the strongest.