Tiger Sub Wars (1988, LCD, 2 AA Batteries, Model# 7-754)

In 1989, Tiger introduced their new "Super Sound" series with 3 new games. All of these featured 'exciting new graphics and game play on an even larger super size LCD.' Each game also featured a variety of 'Super Sound' effects. The 3 initial games released in 1989 in this series are Road Race, Space Fight and Sub Wars. (I'm not sure if additional Super Sound games were released in the following years.) Released in Japan with the Sega brand as Submarine Wars.

Sub Wars: You are in command of the newest nuclear sub, and you must use your sonar and search screen to locate and destroy enemy subs.