During the investigation under Akainu, a particular name was highlighted exceptionally: Flame Emperor Sabo. Being worshipped like a god and igniting the revolutionary spirit all across the globe, Akainu has sworn to "finish them all".
With Blackbeard and Im, we have 2 candidates as endgame villains for Luffy. That is, if Im is a powerhouse and anti Joyboy, but with Blackbeard certainly having a main villain too, which will surpass even the old legends Roger and Whitebeard, who are above Akainu, with Luffy having already surpassed Kaido or being at least equal to him and thus above Akainu.
Is Sabo a fitting candidate for taking on Akainu on Luffy's behalf? Things that speak for Sabo:
> When putting Magma > Fire in the SBS, Oda pointed out that this alone cannot establish the outcome of a fight. How will he prove that?
> Luffy allowing Sabo to take his place in the Dressrosa arena, allowing him to fight his fights and protect Ace' legacy
> Sabo having blamed himself for not being in Marineford when his brother(s) needed him
> Sabo being said to have inherited Ace' will
> Sabo, after destroying Burgess, saying that, although he himself held no grudge, it was Ace' will that expressed itself through the Mera Mera no Mi at this moment, as Ace did not forgive his enemies
Would it be possible that Joyboy D. Luffy entrusts the killer of his one brother to his other brother, who inherited the power and will of his deceased brother, while he himself takes care of the true figurehead of the World Government (Im) on Sabo's behalf? If not, who is Sabo going to fight alternatively?