Scary Pop Up Nyan Cat is a screamer video. It shows the famous Nyan Cat animation along with the Nyan Cat song. However at 2:41 it shows a close-up picture of Regan along with a loud scream from The Maze.
There is also a different version of this screamer with the picture of Regan replaced with Katie Embry from "The Ring " accompanied by two loud screams instead of one.
NOTE: The following video contains a screamer.