When I was a kid, I would sleep in the basement of my house. Every night I would sleep with my little dog. One night I woke up and was just scared for no reason. No bad dreams, nothing happened, not even a noise… I was just terrified. Then my dog goes insane. He gets off the bed and starts barking with his hair standing up, he acts like he is chasing / squaring off wit something… showing teeth, and leaning forward etc. He then chases something I can't see at all into the corner and is barking and trying to keep it in the corner. Needless to say, i'm confused and scared shitless. After a while my dog just calms down and move away from the corner like the threat was gone. It was weird.