In that awkward moment when you see that I'm the Joker too
Captain Murphy isn’t just the Dark Knight. He’s also the Joker.
The braggadocio of this verse brings up fairly recent events in the Comic World (see Nemesis), and as such, if Batman were to become the Joker, the resources and abilities at his disposal would make him far more destructive evil than the Joker himself. Which is in itself an ironic joke.
Basically, what he’s saying is that he isn’t just the hero. He is the villain too, making there more than meets the eye on this “cult leader.”
Could also be alluding to him secretly being Flying Lotus. He’s FlyLo (Batman) and Captain Murphy (Joker) in one, and the laughing behind these words could be him laughing in our faces because we don’t see it.
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