I've been leaning towards Deacon Blackfire and Jean-Paul Valley for
The Batman II lately and base the plot off of "The Cult" with elements of "Knightfall" (specifically, Knightquest and Knightsend w/ Azrael's rise and fall), "Venom," and "Curse of the White Knight."
After the events of The Batman, many have been forced from their homes amidst the flooding and have taken refuge deep within the sewers where they fall prey to the fanatical sermons of Deacon Blackfire, a power-hungry zealot who seeks to control Gotham City. Meanwhile, in order to keep up with his heroic activities, Batman becomes overly-reliant on the steroid 'venom." His dependency to the drug opens him up to defeat, and he soon finds himself bested by Blackfire's latest champion, Jean-Paul Valley--a radicalized military vet who seeks to replace him on the surface as Azrael.
While the newly-promoted Commissioner Gordon deals with the arrival of Azrael, who lacks Batman's zero tolerance policy on killing, the Caped Crusader must must fight through the depths of hell itself, unable to call upon his allies, to overcome his own demons to save Gotham City.
With this storyline, Azrael would probably be targeting Penguin’s operations, or another mobster. And probably want to throw in a character from the Rogues Gallery for him to brutally murder, so to highlight his descent towards madness.
or just go with a Predator lol