There have been a few but... –
One year I was working in a dark maze portion of a haunt. People would walk in from a well lit area and, pretty much without exception, stop cold. I have good night vision to start with and after being in their for a while, I could see quite well. I had my face and hands airburshed black and wore all black. For all intents and purposes, I was invisible. I would simply walk up behind or beside people and whisper into their ears. With good victim selection, this was very effective.
At the end of a slow night, two college age couples came in. I heard one of the girls use the other girls name. So to the first girl I whispered "we can see you, but you can't see us" and gave a low laugh. She gave the perfect scream as I moved to the other girl and whispered "Tina! You have been chosen to stay with me." She bolted, the guys nervously laughing went after her. I could hear the whole group screaming through several scares. Since it was slow, I took a shortcut to get ahead of them in the maze. I stood up againt the wall, right under a black light near the emergency exit. The whole group, breathing hard. The whole group stopped not two feet from me. The 'tough guy' in the group said, 'good, some light, you guys need to pull it together, lets rest here a moment.' He then put his hand out to lean on the wall, only he stuck it right in the middle of my chest! I jumped forward and shouted "You were warned not to touch the monsters!" He collapsed on the floor blubbering "I'm sorry, I didn't mean too, I'm sorry." Meanwhile, the other guy darted out the emergency exit and was gone. Both girls screamed their heads off, then realizing what had happened to the guys, laughed their butts off. I think the guy may have needed psychological help down the road, but what the hell. It was a great scare!
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