Right around the film's release, a fourth crossover series comic book series event between Batman and the Teenage Mutant Ninja Turtles began publication (which is the third overall released by DC, as IDW only released one of the previous crossovers). See more
And then they were gone. It all happened so fast. And I didn't have time to, you know, Batgirl up. Those things, they were like lizard men or something. They took the generator. Into the wrong hands, it could blow up a city block. We have to stop them, Batman.
Whatever they are, they're going to regret stepping foot in Gotham.