It looks like to me rather someone wearing clown makeup or wearing a luchador mask. I am wondering if the story behind it is real. Sounds kind of weird that someone would let kids into an abandoned building to BS around as they say. If the building has been abandoned that long what would be worth so much that they would really have to lock up? If you watch it closely there is a smudge that matches the imprint of the face. You can pretty clearly see the eyebrows and nose in the smudge.