"An impossibly large alien craft."
|Main Dangers:||UFO's, Alien Tanks, Alien Lord and Alien Queen.|
The Mothership is a bonus level that can be accessed from the alternative exit that always appears on level 3-4. It appears in a futuristic structure that extends from the ceiling, with a door at the top of the structure.
It is a very volatile place - automated defenses and explosive enemies will tear the level apart to get at you, and the Alien Lord's psychic attacks will more than likely kill you immediately if you are hit.
Unlike other levels, this level goes in reverse. You will enter the level at the bottom of the map, and the exit will be at the top. When you exit, you will return to the beginning of 3-4 and be forced to do the level again before entering the Temple, meaning you will be forced to complete an extra two levels on a standard playthrough.
The Robot spelunker can be found inside a capsule here.
The tunnel man can appear to make a shortcut to this area, however the temple actually gets unlocked instead if you give him the required items.