During our investigation of the Trans Allegheny Lunatic Asylum this past summer, as we got to the last floor, the 4th, our guide had recommended we just sit quietly and we would most likely hear a lot of disembodied voices and strange noises.
After walking the entire floor, we decided to follow the advice and we sat on the floor of a long hallway with nothing but our digital audio recorders, just allowing our eyes to adjust to the darkness and listening for any sounds. At the end of the hallway was the door to the central stairs which was allowing just a faint amount of light through the narrow window. Looking down the hall, we kept seeing a shadow covering the window in the door. We knew it was nobody in the hallway as we were the only two on this floor at the time. Our guide had taken a break and left the floor entirely.
I couldn't believe what I saw next. I saw a creeper shadow figure come out of a red door on the right side of the hall and crawl towards us and across the hall into a door on the left.
We then went to take a closer look at the room where the creeper appeared from. We discovered the door was blocked by another door laying on its side, making it very difficult for an animal to emerge from the room. We looked into the room where I saw it enter and we found nothing there either.
At this point, I was seriously doubting what I just saw and even came to the decision that it was my eyes playing tricks on me as it was approaching 4:30 AM.
About 10 minutes later, our guide returned and asked if we had been experiencing anything. We told him about the shadows at the end of the hallway covering the window and asked him if he was in the central stairway or not, which he said no as he was outside the entire time until he just returned. He then proceeded to tell us what another guide had experienced on this floor recently. He told us another guide saw a shadow creeper figure appear from the red door just up on the right and craw across the floor towards us into a room on the left. What he just described was exactly what I just saw.
This totally gave me validation to what I saw that night and it's something that I will never forget.