It almost looked like it was trying to surround them. Mercy was moving backwards fast, looking from side to side, trying to judge size and movement. They weren't going to make it. At this pace it would close off around them.

But maybe if she timed it just right, gave Billy a shove past the edges, then bolted herself - her faster-than-human speed might just let her clear it too.

Almost without thinking, she shoved him as hard as she could, closing her eyes for a second in relief as the additional impetus helped him make it through. Now, if she could just move fast enough...