UFO Bases will be another structure in the Generate Structures button. UFO Bases are very high protected by aliens. If you can sneak your way in their watch out. Aliens work in day and aliens protect at night. The entrance is five blocks wide and four blocks tall. The base will intersect tunnels, tunnels that take you to many spots. These tunnels will lead you to the lab, buliding area, sacrifice area, or the best of all UFO. The UFO doesn't fly but its huge with a couple of treasure chests that include diamond, emerald, diamond blocks, emerald blocks, diamond tools. The UFO has three rooms. The chest room, disect room, and the flying area control room or FAC. How to find a UFO base you will find E.T highways. Thats all.