The dark figure also known as Dark Kleiner is a entity that most likely predates the map and can appear on other maps. He is a neutral entity that stalks the player from afar in various locations. He has the model of Dr. Isaac Kleiner [1] a scientist from Half-Life [2]
If touched by the player the sound squeal1.wav plays this sound originates from "the clock" from the half life 2 beta [3] and then the player is teleported under the map and killed with the sounds of children playing in the background