Tomahawk 777 (Revision 1) - MAME - Shoot 'em Up

You play as a submarine. There are alien space ships draining the world's water. Earth needs water though, so you've been ordered to open fire on the invaders from space. They move in a simple “back and forth” formation, so it should be easy to hit them. The game's name comes from the type of weaponry you use to defeat these alien space ships. They're Tomahawk missiles, real powerful stuff, able to blow up even the strongest alien ships in a single blast.