The ad-supported version, get the full version to avoid those pesky ads!A UFO has landed near Area 51, ready to attack America's most secret military compound... and to take back the flying saucer that crashed near Roswell, New Mexico.Destroy the UFO threat as it sends a steady stream of giant plaa shooting robots towards your air force base.Take down the enemy with your machine gun and missiles, or even ram them if you get desperate enough.