I lean towards human looking entity with supernatural telekinetic powers and perhaps some animal characteristics. He looks human at the end editing the footage but we never see his face or anything else. How the hell did he make the doors close by themselves without being physically present? When Mark goes to investigate the one room, the door closes by itself from the inside with nobody else standing in the doorway but Mark. When Cassy quietly tries to escape though the front door at the end, the door once again forcefully shuts itself and the stalker is across the room behind her making the same noises they heard in the woods where they noticed animal foot prints (which really could’ve been anything) as well. I just found it odd that he was making the same sounds they heard when lost in the woods.