Seaquest 99

Objective: Control a submarine to rescue up to six lost divers while shooting or dodging enemy killer sharks and scavenger submarines.

Oxygen Management: Your air supply constantly depletes. You must surface before your oxygen runs out.

Scoring/Rescuing: Rescuing a full load of six divers and making it to the surface awards bonus points. Surfacing with an incomplete load or no divers can cost you a life or a rescued diver.

Difficulty: The game speeds up and becomes harder each time you surface. You start with three lives and earn an extra life at 10,000 points.