Alien (Signal Simulator)

This unnamed species have a small presence on Earth.

Biology
This species has a Humanoid body with an enlarged head, grey skin, and large jet black eyes. While they have never been heard speaking directly, the noises they make when they infiltrate the Control Building reveal their language sounds similar to clicks, chirps, and croaks.

Culture and society
Very little is known of their behavior, though they have been shown to have a stalking behavior, as one of these Aliens can be seen via a security camera spying on an earthling within his own home as shown in the image on the left.

History
They arrived on Earth at an unknown time via a mothership which they buried under the ground for unknown reasons. Ever since they have been terrorizing people across the planet, probing and experimenting on whoever they find.