Killer Croc has appeared in both the "" storyline and its chronological follow-up, "Broken City". In the former, he is infected with a virus that greatly increases the rate of his devolution, 'overseeing' a kidnapping for Hush before Batman defeats him; this provides Batman's first clue that someone else is orchestrating events, as he knows that Croc is too stupid to attempt a complex scheme like a kidnapping. Though Killer Croc was briefly restored to his original form, the Mad Hatter, under Black Mask's orders, implanted Killer Croc with a device that made him loyal to Black Mask and caused the virus to return. Batman freed Croc from Black Mask's control. Croc attempted to take revenge on the Mad Hatter, but was stopped by Batman. Croc then escaped.