I won’t be long, because everything is in the image.
1) No one has mentioned it, but Zaza has two fins located in the same place as an elephant’s tusks ! And her veil is similar to ventral pleats.
2) Which goddess is similar to Zaza? Ganesha (inspiration for Zunesha), whose particular traits are having four arms, an elephant face, a hat with a tip shaped like spheres, pearl jewelry, and a water lily in her hand.
3) On whom does the rain fall exclusively in the mural ? The whale, and no one else.
4) Roger and Oden felt unwell when arriving at Zou, indicating that something huge was watching them, with a close-up of the whale, as if it were alive (or petrified ?).
5) It is stated that Zunesha’s rain is considered a blessing for the island’s food supply and ecosystem, but it also causes floods.
6) On Zou, Nami’s dress is specifically said to have belonged to someone important and to be a national treasure. Sanji perceives her as a goddess in this outfit, and Chopper wears a crown with a pearl necklace identical to Zaza’s.
7) Vivi currently wears an outfit with the SAME visual/color scheme as a whale, and she has often worn striped dresses like a whale’s ventral.
8) So : Is Zaza actually petrified on Zou ? Is she in her original state, not even transformed into a Devil Fruit ? (Easier to swim as a whale...) Is someone the user of the fruit in a Zoan form ? Is she connected to Lily to complete the quartet of gods between Imu (Forest) / Joyboy (Sun) / Davy Jones (Earth) / Lily (Rain) ?
9) And therefore : Will she be unpetrified by Boa, knowing she is likely a successor of Lily as the empress of Amazon Lily ? Then will she naturally be tamed by Vivi staying in her original form ? Or is her fruit located on Zou and will be eaten by Vivi ?
What do you think ? Does this inspire any other theories ? :)
(By the way, Boa and Vivi have the 2 biggest foreheads of One Piece, they have to meet and do something BIG as their forehead together.)
