The parallels Oda has put in Thriller Bark arc are insane. Could be reaching, but take it as you will in understanding the amazing foreshadowing Oda has put into Thriller Bark.
1st Parallel
-The situation with Absalom and Nami in the bath compared to the situation with Stealth Black Sanji in the bath house. And, of course, Sanji wanting to be invisible, got made into a reality in Wano.
2nd Parallel
Stitched up Pig holding 2 swords.
And as you may know, Pig God after he was cut by 2 swords from Oden, he had to be stitched up.
3rd Parallel
As you know, there’s a theory about some Rocks Pirates member being zombies.
And in Wano, we were introduced to Rocks Pirates.
4th Parallel
Foreshadowing of Kaido’s Numbers which were originally created on Punk Hazard.
On a side note, this could foreshadow the Zoan Army.
5th Parallel
According to Big Mom, the Numbers are failed recreations of the ancient giants.
The Numbers have been noted to be just as large as the ancient giant Oars, who at 67 meters stood three times taller than a typical normal giant; they also all possess horns.
6th Parallel
Chopper commenting on Lola’s charging
Whitebeard commenting on Oden’s charging
7th Parallel
Foreshadowing Kiku?
8th Parallel
Zoro cut Kaido like Kuma.
9th Parallel
Thriller Bark is where Luffy obtained a ridiculous power-up, the Nightmare.
Wano is where Luffy pulled the most ridiculous powers of Joy Boy’s Nika.
*Theory by LogicalGoal5