Floating skulls that still had the eyes in the sockets. But the eyes weren't just dead, they were bright, piercing, and watching like they could see everything at once. They also had long, slithery tongues coming from a void somewhere inside the skull itself. They would float around and some people were caught, and the skulls would choke them with their tongues and then sever the head...
When I was a little kid, about 5 years old, I started having recurring nightmares of a man/creature that I called "the Fraid." The Fraid lived inside my wall and he would smash through and try to kidnap me. Preceding his bashing through my wall would be the sound of his breathing, like someone breathing very deeply in and out through clenched teeth. He would also say nonsensical things that freaked me out for some reason, like, "Tricky branch!"
(My co-worker) was about seven feet tall, grey skin, and muscular. Its left arm was fairly normal, but its right arm terminated in this gigantic bone-spike that had two small spikes protruding from the sides, like three "fingers." Its eyes were yellow but...hollow, somehow. Half the skin of his face was gone, revealing his skull, and on his chest, some of the skin/muscles had sloughed off, revealing his bloody ribcage and a beating heart...
I used to have nightmares of me sitting perpindicular to a flight of stairs and E.T. would slowly walk down them, with his fucking scary head and that weird neck turned toward me and just staring at me as he decended the steps...
I woke up in my bed but the sky was very dark and everything seemed very awkward. I then stepped out of bed and the ground was very juicy, I looked down, and my bed was placed on top of a gigantic hill of dead children.