The front of the herd was approaching, trying to push past her. Phaedra shut her eyes. These. Were. People. Live people. They were just being ridden by whatever was behind all of the things happening at the fair. Or the Hellmouth. Or both.
That didn't mean they didn't want to hurt Sam.
So stabbing would have to be okay.
When her eyes opened again, they were feral green, and the two zombies that tried to push past her first were each nursing fairly deep cuts--one on the shoulder, where he'd tried to push past, the other at the waist. They wouldn't be fatal; Phaedra knew what she was doing. And as long as they were undead, all they'd do was slow them down.
"How fast can you run?" she asked Sam over her shoulder, backing up and away from the horde faster and faster. "If it's not fast I'm going to have to carry you."
Happily, it seemed the corn maze actors took their zombie cues from the slow-moving school of undead shambling. These things weren't running. They were dragging limbs and limping. But there were still thirty of them.