WARNING: The following contains major spoilers for Batman #85 by Tom King, Mikel Janín, Hugo Petris, Jordie Bellaire and Clayton Cowles, on sale now.
The finale of "City of Bane," which brought to a close writer Tom King's run on Batman, was an emotional one, with the Dark Knight halting the villain's assault on Gotham and on the Bat-family. At the heart of this was Thomas Wayne, the Batman from the Flashpoint universe, but after weeks of mind games and mental torture, to say nothing of the death of Alfred Pennyworth, Bruce emerged on top and began to chart a life forward with his loved ones, Catwoman in particular.
However, it wasn't a totally happy ending, because in the epilogue, by writer James Tynion IV and artist Guillem March, the Joker is finally preparing to unleash greatest weapon: knowledge of Batman's true identity.
Fans have long thought the Clown Prince of Crime knows who is beneath the cowl. Suspicions arose from Alan Moore and Brian Bolland's 1988 graphic novel Batman: The Killing Joke that the villain was aware that Barbara Gordon was Batgirl, and that Jim Gordon may have been connected to the Dark Knight on a deeper level, even if the commissioner was keeping that to himself.
Then came the 2012-2013 story arc "Batman: Death of the Family," in which the Joker made his way to the Batcave and tortured Alfred, compounding that the Caped Crusader's archenemy knew more than he let on.
This story now finds Joker in his lair with his goons just as Superman goes public with his identity. The thugs are stunned that the Man of Steel could masquerade as someone like Clark Kent for so long, and they believe Superman's enemies are idiots for being played so easily.
Joker takes the phone to see the buzz about this "ordinary person" who confessed his superhero identity, and one of the criminals, Henry, begins to make a valid point. He believes the Joker is holding Batman's identity for some big play, but if the Dark Knight outs himself like Superman did, that information will become useless. Joker questions whether the info will actually be worthless, but he nevertheless doesn't like Henry thinking so far ahead. He attacks his lackey with razor blade chains, and admits a punch line only works once -- and that time is indeed running out for this trump card.
The Joker agrees it would be the final battle, but he doesn't know if he's ready to bring this dance with Batman to a close. Most importantly, he knows this endgame would result in one of them dying. The kicker is, though, as the simpleton lays in a pool of his own blood dead, Joker actually loves this plan as he says it out loud. It has a ring to it and he realizes it'll be "a lot of fun," so Batman better get ready, because after what Bane and Thomas unleashed, his family may not be equipped for this new Identity Crisis Joker's preparing to drop on House Wayne.