Batman (Damian Wayne) – Batman #666
SPOILERS
Remember that mindblowing 100% Knightfall secret ending of Arkham Knight? A prominent theory is that this new Batman is making use of Scarecrow’s fear toxin against Gotham’s criminals – how else would he able to conjure that hellish visage? To be honest, that was not my first conclusion. My brain instantly raced to another Batman from comic book continuity. In Batman #666, the reader is introduced to a dystopian Gotham City where this future’s Batman is none other than Damian Wayne, the son of Bruce Wayne and Talia al Ghul, grandson to Ra’s Al Ghul.
Featuring a new costume with seemingly occult visual motifs, Damian Wayne is the next Batman after having failed to save his father. As a result, Damian’s Batman is far darker as he is willing to torture and kill criminals. Most notably, he possesses a range of bizarre supernatural powers (such as an accelerated healing factor) and it is implied that Damian made a deal with the Devil to attain immortality and great & terrible powers to fight and save Gotham City.
While I made the case in another feature that Damian Wayne could potentially exist in in the Arkham continuity, in the end it all boils down to mere speculation and not likely to hold up. Nonetheless, it is a fun theory to toy with in imagining the new Batman at the end of Arkham Knight being fueled by the sheer power and terror of Hell itself.