Barbara arrives in the midst of their battle, if a battle it could be called. She barely glances at the spectacle - a spectacle, made of murder, it turns her stomach - as she approaches the dome, a safe distance from other spectators.

That's when she starts throwing batarangs. They're large than usual, and made to explode on impact.

They do not, of course, do any good at all, but she keeps trying anyway, long after it no longer matters.