Basically, devil fruits was the result of the technology of an ancient civilisation that was recklessly using their technology. As a bi-product, just like how devil fruits are born from people’s dreams, a devil was born out of the people’s fears and nightmares - this was the birth of Mu.
I believe Nika originally lead a force which fought against this ancient civilisation but when the demon came out, he became the enemy of everyone and was swiftly defeated but before completely disappearing, it split it’s soul into 3 fragments, each becoming it’s own devil fruit which is they will never meet. A villain consumed one of those devil fruits and fought Nika after taking control of Pluton and their fight destroyed the first world.
In the second world, Davey Jones and Imu both consumed the other 2 devil fruits and each controlled an ancient weapon too compatible with their God fruits
But in this world, all 3 will come together bringing back the actual final villain, the primordial demon, Mu who is the fusion of the earth, rain/sea and forest Gods
I believe Nika originally lead a force which fought against this ancient civilisation but when the demon came out, he became the enemy of everyone and was swiftly defeated but before completely disappearing, it split it’s soul into 3 fragments, each becoming it’s own devil fruit which is they will never meet. A villain consumed one of those devil fruits and fought Nika after taking control of Pluton and their fight destroyed the first world.
In the second world, Davey Jones and Imu both consumed the other 2 devil fruits and each controlled an ancient weapon too compatible with their God fruits
But in this world, all 3 will come together bringing back the actual final villain, the primordial demon, Mu who is the fusion of the earth, rain/sea and forest Gods
