So like what happen to it? :| Will Kishi show it? I mean he hinted that it was to stop Obito if he got out of hand, but since Obito is on his deathbed do you think this "Trump Card" will come into play?
Who knows. But if one things for sure, its that Madara definitely has plenty of tricks up his sleeve. As Kishi wouldn't save him for last to fight the ENTIRE shinobi alliance if he didn't.
I'm itchin to see just exactly what this trump card is.. Controlling hashi would make some serious trouble for the SA. It could be his own summon or some unseen, powerful jutsu.