Naruto
I am going to spit out a major plot device like tobacco and not give a fuck
I was half-expecting him to vomit the guy Kabuto had sacrificed for the Edo Tensei: "there, I acknowledged it, you nitpicky readers! and he can just spit the corpse out because
magic! much better now!"
As for the mystery guy, I'd say "hey, we know of an Uchiha who got his heart pierced and mysteriously survived anyway, remember! Hashirama had apparently seen/heard/felt something right before passing out, maybe it's the same guy (whose hobby apparently is to save Uchiha psychopaths' lives)? let's connect the dots!"... but yeah, it's Kishimoto, so I probably shouldn't expect much in that area (remember how Obito bragged about having manipulated Yahiko into creating Akatsuki? or how he used to be Mizukage kinda sorta? yeah). Plus, those look like dirty "I've just been a fight" feet...
Still, I'd like to know how Madara survived that old fight/wound. Surely, considering how they were so sure Madara was dead, Hashirama didn't wake up to a distinct-lack-of-corpse, right? So there was a fake corpse? And it fooled everybody?