To say the Batman: Arkham Knight DLC has been lack-luster would be an understatement. Other than the Batgirl DLC, nothing really of any meat has been given to players. Well, that appears to be changing December 22nd when the DLC "Season of Infamy" hits.
The DLC will feature new levels and classic Batman villains: Mr. Freeze, Killer Croc, Ra's Al Ghul, and Mad Hatter. The final Arkham Insider of the season talks about the new DLC (the talk of it starts at the mark :54 mark with a good look at the Ra's portion of the DLC, while 3:50 for the other parts):
If that wasn't enough at 9:21 Rocksteady hints they maybe aren't quite done with doing Batman games. Is that good for the kind of lackluster way the game ended up (too much Batmobile, not enough Batman? DLC lasting less than ten minutes for the most part save Batgirl which was thirty)?