You are part of the crew of one of the few
surviving submarines following a devastating Nuclear war. Your
original underwater base is in an area now controlled by the enemy.
Having found a new base you must try and make as many hazardous
trips as possible into enemy held territory to remove supplies from
the shelter in the enemy zone (Home 1) to a safer shelter (Home 2)
in a non enemy controlled zone. Your submarine has a leaking ballast
tank and can only remain stable by pumping air into this tank. As
you proceed through each mission the enemy will set mines at random
heights and later will try to impede you by raising nets. There is
no limit to how many missions you make but it is harder as you
progress through each skill level.
The joystick will control all movement of the
submarine. Left and right controls the forward and backward
movement. Moving the joystick up will force air into the ballast
tanks. Too much air will force the submarine to rise too quickly
whilst too little will cause it to sink to the ocean floor.
You have 3 lives only and must avoid hitting
mines, nets, rocks or the sides of the screen and must not rise to
the surface as the air is contaminated.
You gain points for staying mobile and get 100
points extra for each successful mission completed. Your air supply
is limited so you must strike a balance between continual movement
and conservation of air.
The opening screen will ask you for a skill level
from 1 - 9. Simply press the appropriate key and the screen will go
blank for a few seconds before the playfield appears. At the end of
each game your score will be displayed and you will be given an
opportunity to select a new skill level.