"By the looks of it, she's terrified to death that she might die from an unknown disease." Pitch interrupted, "Listen to me closely, there is a very high probability that you've all been infected by a black curse. Nessa, you've been known to specialize in shadow magic, so you and I may be immune. Kristoff and Fredrick, you two aren't so lucky."
Kristoff stood up, shaking as he stood. "Professor Pitch," Kristoff spouted, "Why does Jack hate you?"
Pitch ignored the question, he took out his surgical kit and began collecting blood samples from the unconscious students that still laid in the clinical beds. "Not now, we have more important things to worry about."
Before Pitch could begin collecting the blood samples, Kristoff grabbed Pitch by the arm. "Pitch, we're dying. Tell us the truth."
Pitch sighed, "Don't be dramatic. You're not dying, you're simply converting."
"What?" Kristoff asked.
"A year ago I began an experiment that involved controlling people's dreams. It was meant as a surveillance precaution to know what each and every students intents and desires were." Pitch waved a hand over Kristoff, his black hair faded back to a golden blonde. "It worked for awhile, we were able to know exactly what all the students were thinking. Eventually though, Maleficent wanted to push the limits of my experiment."
Pitch takes the palm of his hand and forms miniature running horse. "She wanted to know if she could intimidate her students into thinking a certain way. Change their personalities and desire to become something more like... her. It didn't work obviously, to change someone's being, you'd have to completely alter their memories into something different. Change the way they were raised, instill certain events to warp them into something else. It could take years of work to change ideology of a single student."
The shadow in his hand morphs into a hospital bed. "I warned her it wouldn't work, the only thing that happened was that a few students fell into commas." The thing about truth, is that if you give people half truths, people will completely believe you.
Pitch's shadow turns into a black radio antenna, "She then asked me to create a hive mind, to allow her to instill her ideology into the other students. Very much like propaganda television." All he has to do, is make these kids believe Maleficent was the enemy. "I did as I was told, and of course the students didn't buy it. They just thought they'd been spending too much time studying."
Never ask for the truth from a villain. "In the end, we found out a morbid truth to my experiments. The magic I used to control dreams, caused a leak in the student's powers. Their powers and abilities, leaked into the air around us. It was draining the students of their life, and we were forced to stop it."
Pitch's shadow transforms into a giant worm. "Apparently, those nightmares have leaked into the caves. This curse, is a result of this school's nightmares."