In spite of her fear of the Joker, Carrie had insisted on coming. Not only for Jason and Cass, but for herself. She'd wanted to do this. So she reminded herself of this fact as Nightwing took a flying leap and jumped into the middle of some thugs. There wasn't anything about this operation that wasn't like any other bust. Except for the crazed clown on the loose who was hungry for their blood.
Carrie had memories of the Joker. The only time she'd dealt with him in her world, he'd killed some of her friends, along with dozens of innocent kids. He'd died at Batman's hands at the end of that day, much to Carrie's relief. In the deeper recesses of her consciousness were memories that didn't quite belong to her. Memories of murder done by a Joker copycat and torture, at his hands.
Carrie took a very deep breath and smoothed out her cape before dropping her hands to her side. She could freak out later, when they were all safe.
At the sound of Dick's voice, Carrie had jumped down from her spot in the rafters and landed on a thug. They were here to distract, so Carrie knocked hard into the solar plexus of another thug and sent him flying backwards into a pile of crates. She found quickly that the guys the Joker worked with weren't terribly bright. Aware of Dick beside her and Batman somewhere above them, Carrie smashed the heel of her foot into one thug's kneecap, and looked around for the man of the hour.