Comment by King of Cans on One Piece - Chapter 1182

@King of Cans Idk, to me it sounds more like Imu has been alive this whole time while the old Nidhogg died and was "reincarnated" in this world as a devil fruit

@Shinzo
that would imply Imu is aware of the mural, and the idea of calling eras as worlds... there's no reason for him to say "in this world" if he don't mean a actual different planet... may not even be a planet but a different realm or dimension.
for sure he is alive at least 800 years, and he also know nidhogg. but that doenst mean he is from the blue planet.