This is one of the Vegrons Multiple Living Machines. It hunts down and exterminates any humans it sees. The only way to kill it is to shoot a missile just under it's "eye".
About this creation
This is the "eye" of the Exterminator. You can see two testicles and the week spot in this picture. Once you see this thing, pray you have a heavy trooper in your squad.
These are the legs and "arms" of the Exterminator. The two sharp legs puncture you and inject a type of stunning poison that doesn't make you move. It then would carry you to one of the Veron's "Factories" and make you into a Vegron soldier.
This is the last thing you see if caught by this thing...