Pretty much everyone is taking an educated guess because in the new gen we don't know who has acquired what to be honest. I agree 8 gates Lee if he has it but if we don't count that because he dies from it, I would guess Oro or Kabuto. Oro has been alive and we all know his goals are to master every possible jutsu also the man doesn't age so no doubt he's grown stronger.
But of course, there is still one dark horse. And it's that dude IRUKA.
@bold lol wut? Size has nothing to do with it. Are you serious? HUGE chakra reserves must come with being in their bloodline, being that the 3rd and 4th are father and son. Must be heriditary.
I'm well aware that Darui has an impressive amount of chakra. Just not nearly as much as his two former predecessors.
I'm not saying you are wrong, but you have little to back that claim up. Darui has had HARDLY any of his current potential displayed, that goes for most of the kage aswell.