"Let him in and he'll save us all!" (Twisted!) "The alien may be here to invade the planet, but you should probably welcome him. It may just save us from an even more dire situation..." (Gold)
The game's purpose is to make a martian land on Earth. To do so, the player must move the humans in the two first levels to make him land on an empty space, and the martian in the last level to protect the earth from the falling meteor.
1st level difficulty: The martian descends horizontally, and the empty space starts onscreen.
2nd level difficulty: The martian descends vertically, and the empty space starts offscreen.
3rd level difficulty: The martian is on Earth, and the player has to move him to hit the falling meteor that descends diagonally. The martian starts off farther offscreen.
1st level difficulty: The martian descends diagonally, so its landing location is small.
2nd level difficulty: The martian descends vertically, so its landing location is wide.
3rd level difficulty: The martian is on Earth, the player has to move him to hit the falling meteor. This is done from the same perspective as Level 1. The martian starts off offscreen.