Mariner

Mariner is: a horizontal scrolling shooter arcade game, that was released by Nova Games (under the name "Amenip Corporation") in 1981 and licensed to US Billiards for US manufacture and distribution under the name of 800 Fathoms; it utilizes a Zilog Z80 microprocessor (running at 3.072 MHz) with a General Instrument AY-3-8910 (running up at 1.78975 MHz) for audio. The player must use an 8-way joystick to take up control of a submarine, with a trigger to make it fire torpedoes, and a thumb button to make it drop missiles on various enemies - and, as well as not being able to withstand contact with any enemies and their shots, it is also unable to withstand contact with any of the underwater terrain, which can severely limit its mobility. At the end of each stage, an enemy boss submarine will appear, and its firepower is far greater than your own; once you have managed to fire enough shots at this to defeat it, you shall proceed on to the next stage. There are a total of five unique stages for the game.