Will's instinct is to reach out and pet Hester (because purring cat), but the same instinct that told him which copy to target tells him that touching Hester would be Wrong, so he doesn't. Instead, he continues to watch her warily. "I - I think so? I don't know, I've never done this before," he answers, a little helpless. Because he wants to know how to fix this, he does, but up until now he had no idea he could just Know Things like this. It's new.

And then suddenly he yelps and grabs Lee's arm, tugging him backwards a few inches and out of the path of a very sharp and dense icicle.