The goal in Sea Wolf II is to out-shoot your opponent, trying to sink as many ships as you can with your sub's torpedoes. The trick is, you can only shoot four torpedoes at a time before you have to pause to reload. So, if you don't manage your ammo with care, you can miss out on target opportunities. The one who sinks the most ships in a set amount of time, wins. You can play against a friend or the game's AI, “Captain Backstein” and have a choice between using joysticks or paddles.

From the title screen, press to get to the game options. You can choose the number of players by pressing or and on the joystick. Change the duration of the round with and or and on the joystick. And lastly, choose your controller type (joysticks or paddles) with .

In the game, move your sub with the joystick pushing and and fire torpedoes by pressing the button.