"Text. I don't want them to know it's me." Because if they knew it was him, there'd be no way they'd want to meet him somewhere. "Figured I'd make it look like a mass text announcing a party to get them to meet me somewhere, then I'd interrogate them. There's a mask I wear when I DJ, so they don't have to know it's me, and if I really want to freak them out enough to confess, I can always call up a swarm of rats."

Which, considering that was the murder weapon, it would theoretically freak them out more than normal. He figured since they were significantly younger than the teacher, they'd be less likely to have heart attacks and die from the experience.