Hello I'm new here and I got some ideas. But before i post all of them, I first want to put down one idea so I can look if the others are any good. I'm not sure if it has been done already, but here it is.
It's a item (not sure what yet) that sucks up light. And ofcourse because there is no light anymore in that room you won't see anything, you'll be blind. If you get exposed to the item for too long it may cause permanent blindness.
It has probably been done already but I just wanted to be sure.
Thank you for the time.