Information!
“What’s that?” the witch asked him. She looked a little cold, and a little scared, and really mad. Timmy didn’t know why. She hadn’t gotten hit with elf-shot.
“None of your business,” Timmy said automatically. But then he realized he didn’t actually care if she knew. If she was a witch, it was probably safe to tell her. “Yeah, sorry. The elf will leave if I don’t jam this thing into the fence. It’ll keep it in.”
“How? Is it a spell? A magic item? Some kind of artifact?”
“Uh. I don’t know?”
“How can you not know?”
Right then, there was a faint zapping sound, and an entire section of the fenced-in area went into shadow as a couple of lights shorted out. Jimmy was already running towards it. “I don’t have to know! I just have to know how to use it!” he said, over his shoulder.