Just like Oden

Hmm. You're right, my bad. Let me delete my answer then.

If you go back to the train station arc, you can see a demon pushes it's tentacle down his throat... So, he was impregnated.

I wouldn't say it's a filler, just transitory.

Me too 🥹

There seems to be an "unknown" weapong capable of raising the sea levels, and it also seems it's in the hands of the World Government. I know it sounds irrational because water can't be created out of thin air, but this is a universe where devil fruits apparently materialize such irrational ideas just because some one thought about the posibility (remember Vegapunk's theory about the origin of the fruits?). Maybe there is a Devil fruit or a weapon that can manipulate reality or literally create water. About how the sea level didn't rose after 800 years, maybe it's because they didn't need to do it since Joy Boy was defeated in the void century, and since, no one has ever dared to oppose the Word Government (until now ofc).

Unlikely

Finally caught up... From chapter 0 to tthis one

Maybe ingenuity