I know this comment is short, to the point, and doesn't bring reason for me to start a rant, but just because I feel like it and have some strong feelings against the opinion:
At the point we are in during Wano, it would be extremely convenient for Rayleigh to show up (not to mention I'd hate it for a couple major reasons). As far as I can remember, the public is not aware of Luffy going to Wano. Granted, Rayleigh should be intelligent enough to put the pieces together when it was announced that Law + Luffy joined forces, and defeated Doflamingo, but that'd be quite convenient for him to figure out Doflamingo and Kaido's partnership in exact detail.
As for the reasons why I would despite the idea of Rayleigh showing up to help Luffy:
- As I said, it would be extremely convenient for Rayleigh to put all the pieces together with what limited information he would have. Limited information about the SHs have been released to the public, and only about the Law/Luffy Alliance, Doflamingo's defeat, and Big Mom's "defeat".
- Rayleigh selectively traveling to Wano all the way from Sabaody doesn't seem very likely given that he is retired and hasn't been known to go far from the archipelago. Him hopping onto a ship, going through Fish-man island and a huge chunk of the New World merely a few weeks after Dressrosa news spread around the world. And I doubt he put this all together mentally, found a ship, traveled to FM Island and like half of the New World in the span of a few weeks. Also consider the fact that Luffy's group had been in motion for the majority of the trip, and only stopping at islands for a few days each. Rayleigh would
- It's never been implied that Rayleigh has left Sabaody or entered the New World during the Reverie/Post-Reverie sections, so it would be terrible writing as it would seem that Rayleigh was just thrown into war for PIS and Fan Service in one package.
- So many people are available to save Luffy already (that would make far more sense given previous chapters and keeps the stakes of the war high if it isn't anyone particularly game-changing)
- And the reason I would hate this the most: Rayleigh saw Luffy off in Sabaody and acknowledged him as the person "Roger was looking for" (WB mentioning this before his death). His last words to Luffy were for the boy to "rise to the top". He believes and hopes that Luffy will surpass Roger and obtain the One Piece (Which apparently Rayleigh's generation failed to do as they were "too early"). Rayleigh coming to Wano betrays the trust and expectations he put on Luffy. His character would not respect Luffy's on the level in which was already established. Rayleigh has never looked at Luffy as a "son" of his. He looked at him as the future. It would be wrong for Rayleigh to intervene in the future's efforts as the old generation should let the new generation fulfill what they could only dream.
This comment dragged on more than I expected, smh.
But I do think the most likely people to save Luffy are the Heart Pirates (but those are not worthy of "concealment" (via spoiler) as that's the most expected), A member of the SH Grand Fleet (Harjudin being the one would be an excellent choice since he'd be the perfect catalyst to lead into Elbaf's arc), or potentially even another Whitebeard Commander (since it is entirely possible that Izo and Marco brought someone else for them, and revealing this spoiler would inform readers that there are even MORE WB pirates are present. And it would most definitely be that shark fish-man commander)
