Killer Croc
Gotham always had that survival of the fittest, or dog eat dog vibe, and Killer Croc is the very embodiment of those themes, considering he is a cannibal. In the recent episode "˜A Bitter Pill to Swallow" the show introduced Eduardo Flamingo, aka Flamingo, who had acquired a taste for human flesh. It would have been far better to introduce Waylon Jones aka Killer Croc this way. First of all, we have seen some of the shadowy operations going on in the Wayne Enterprise, where they experiment on people. So, a man with sharp teeth and thick crocodile-like skin appearing wouldn't be as farfetched as it would have been in the first season. Moreover, he would be one of those sewer villains like Blackfire, and like Bane in the Dark Knight Rises, and so far the sewers have remained unexplored in the series. Come on GCPD, it's time to get your hands dirty, or dirtier at least.

