The planet LRV 1168 is registering high levels of toxic gases released by underwater tunnels. You and a friend mount your aquaglyders and go and investigate. Problem is, there is a large beast in the depths who doesn't like strangers going through its tunnels so he has sent its minions to destroy you.

Scorpius is a 1 or 2 player side view horizontally scrolling shoot-em up. You and your friend can play at the same time.You use the joystick to steer your craft and the fire button to shoot your weapon. Occasionally a P or S appear. These can be shot to change the letter and once collected will upgrade your speed or weapons. As well as the playing area you can also see your score or lives.