Fake hand costume
Have you ever seen those costumes where there is a fake hand attached to outside of the costume, so that way people don’t realize that one of your real hands is hiding inside the costume? I had I costume like that once for trick-or-treating. It was a witch costume, and attached to the costume was a plastic pumpkin. I was wearing a glove on my right hand while the matching glove was stuffed and attached to the left sleeve of the coat and the pumpkin, so that way it would look like my left hand was holding the pumpkin. But, my real hand was inside the pumpkin with a spider puppet. I would hold the pumpkin with my right hand and ambush people putting candy in the pumpkin with my left hand. At one point a young child was giving me candy and I scared him so bad that I felt bad so I opened up my costume to show him that my real hand was inside the costume. But, then his dad decided to mess with the poor kid, and just as the kid came to get a close look the dad screamed “oh my god, she’s got three arms.” The poor kid freaked out and ran back in to the house, while the dad laughed.