Carnivora
My companions and I arrived at this facility midday, and it was quite busy as it was still active. There were a few "disused" buildings on the property - I use the word disused in terms of buildings being used occasionally, with power, running water and the like. There were one or two really abandoned buildings up on a hill, so they were the target today.
Upon entering via a cramped basement, we searched for a staircase leading up... and suddenly we heard a loud thump from the floorboards above. We all froze and listened. It started up again, this time in succession, with a clicking noise just after, thump click, thump click... it was definitely an animal pacing back and forth upstairs. A large animal with giant claws.
We banged on the boards above us to try and scare it off, but we didn't hear it run away, the noise just stopped. We waited a good five minutes, then decided to head up. I grabbed a large metal pipe just in case whatever it was did not leave.
We scoured the top and bottom floors looking for the beast, but it was nowhere to be found. The building was quite small and empty except for some really neat Posey restraint guides from the 1970's and a small library of nursing books. From these I thought the building to be a nurse's residence or training building and snapped a few photos. As for the animal, I assume it jumped out a window but as to what it was, I'm not sure... my best guess would be a bear or mountain lion - a danger I hadn't really thought about until this day!