Though Christopher Nolan's trilogy is veritably stuffed with villains, he actually made some allusions to the wider Rogues' Gallery of the Batman universe by hinting at several well-known but not present villains throughout his films. Victor Zsasz of course appears in Batman Begins and The Dark Knight as a supporting villain, having killed 15 people (according to the tattooed marks on his skin), and there's also a veiled mention of cryogenics in The Dark Knight Rises when Lucius Fox reunites with Bruce Wayne (a hint at Mr Freeze?). In the same film, there's an obvious allusion to Killer Croc when John Blake is openly dismissed for wanting to investigate the sewers, and Clayface's creator in the comics - Roland Daggett - appears as a secondary villain. Nolan also hinted in The Dark Knight that Batman would meet Catwoman in the third film: The hidden gem comes when Bruce Wayne is meeting up with Lucius Fox for the first time in the sequel and asks about what improvements can be made to the suit following a vicious dog attack. While the armored suit may not stand up against Rottweilers, Fox tells him that he can be sure that it, Should do fine against cats.
