13m 1/4

Connor O'Gaway is a young Irish boy. He signed in Murkwarts, a sorcery school located in the Samoan Islands. Murkwarts is exactly 13 meters 1/4 deep inside a cavern!
Everything seems normal... Until a professor is found dead in the school. She was magically mutilated: mushrooms grew from inside her nose, roots are coming from her ears, and a third leg has appeared in the middle of her back!
Connor has two choices: find the murderer, or flee Murkwarts with two other pupils. No matter the choice, cries of agony will echo inside the cavern...