HM- Killing Horses

She twisted and untwisted her hair. “I’ve never heard a horse scream. Have you?”
I swallowed. “It ... it must have been terrifying. But —”
“Everyone went running to the stable. They pulled open the doors and found the horses dead,” Laura said. “All of
them. Lying against the wall in a heap. All dead.”
“Huh?” I gasped. “Why? What killed them?”
“Panic,” Laura replied. “They all died from fear.”
...
I swallowed hard. “But how exactly did he scare the horses?” I asked.
Laura let out a long breath. Her face was even paler than usual. “You’ll never believe it,” she said. “The farmers
claimed it was all caused by a mask, a hideous Halloween mask.”

-Chapter 6