So Stephanie was here to change the past, and she wasn't alone in the plan to 'exterminate' someone. Barbara was going to ask who it was that was going to be taken out of the picture, but the sudden strong hit caught her off guard.
The punch packed a lot of power, and being struck so close had Barbara seeing stars. Her head was swimming as she willed herself to stay conscious amidst the pain. Her arms struggled powerlessly to swat off her attacker.