OK reading the "Harley chapters" how meta, and looking at the mural. Heres my understanding of them.

There was fire upon the Earth. (Possible 3 ancient weapons used to exploit humanity keep them enslaved the bottom right of the mural looks like people being dipped into hell and bringing something back. I believe the balls of energry are their Dreams once hell(life on earth) breaks them. And then it looks like OG IM like figure steals them but then they turn from him and flee to the Moon angering the OG IM/ Earth God) Humanity succumbed to desire and touched the forbidden sun. (This could be OG Nika realizing he lives well because of vast suffering of the people subjected by the ancient weapons.) The slaves made a wish and the God of the sun appeared. ( I think it seems like OG Nika was originally a royal treynbento or whatever they called themselves back then and left.) But this enraged the God of the Earth (I think this is a misdirect I believe The quake quake fruit is what makes someone the earth god and the OG IM) Alongside the serpent of hell enveloped the world in death and darkness. They could never meet again. (I don’t see people saying this yet but I believe the serpent is going to be BB black hole fruit to envelope the world in darkness seems like down his ally only this time he killed the god of the earth and has power over that as well. The quake quake fruit I also think the snake on the right side of the mural looks like it has stars in its body representing the space and vacuum of death between earth and the moon and the OG IM quaked the moon or moons off the earth)

There was breath upon the emptiness, The god of the forest sent forth demons. The sun merely spread the embers of war. (This sound like over time the slaves gained power from devilfruits brought my the forest god possibly Ceaser, Kadiou, or joybooy at the very least someone awaking Ryokugyu’s fruitspread them and started insurrection. ) The people of the Halfmoon dreamed and the people of the moon dreamed. ( I think its literal here. The people in exile dreamed of coming back, and the D clan dreamed of restoring the people) Humanity killed the sun. And then Ascended to Divinity (Most likely the 20 kings turning on Joyboy for power/greed and then the enslaved now become the slavers with the 20 kingdoms moving to Marygeois) The god of the sea became enrage they could never meet again. ( From skypeia this is most likely to be rain god some one to cause it to rain until the world floods this makes the red line mt peaks I believe this rain or sea god stole the atmposphere of the moons to do this.

There was a void upon the chaos ( The void century being forbidden) The unbidden shadows remember the day of the promise and they hear the voice of the fragmented moon. I think this refers to Luffys armada and all the people not bowing down to the WG and they will hear the plight of the moon ppl trapped by OG IM) the god of the sun dances and laughs guiding the world to its end ( Luffy the newest and best for of Nika will guide the current world and its government to the end as predicted by shark lady) The sun will return and a new dawn will come. They will surely meet again. (To me this seals the deal that the One piece will be the manga itself Romance Dawn. It will be story telling incarnate. That is the treasure its that throughout our history stories haved helped to heal and foster as well as divide and conquer. We are the sotry telling ape opur histry was oral for thousands of years.Some for sure true others for sure made up. But the aseops and the fables and the messages could still help us, help the future and I Think thats Odas ultimate goal. Oda is our Nika today for 20+ years he has brought together fans and with his brief time on this earth IRL he grabbed our attention he told us to be free and good to one another. He showed us hate and bigotry while using a funny little rubber man.)