You have to battle your way past enemy ships, underwater torpedoes and missiles, then dodge the indestructible fireballs and combat dangerous mines. Before you reach your objective and save Atlantis you have to combat all the underwater evils on one fiery screen. Keep your fuel tanks full by destroying the fuel dumps, and beware of crashing into under-sea mountains, which can first be seen on your radar. Change the game speed to suit your own skill level.