Space Commanders II

Space Commanders II is just a Space Invaders clone, but it's interesting for a couple of reasons. First, it is itself a clone of an earlier game called simply Space Commanders; this seems like it was a fan-made copy of that game. The earlier game was of course a clone of Space Invaders, and was included for free with a company's early IBM-PC clone computers as a buying incentive. Anyways, this monochrome version of Space Invaders plays decently, although for some reason your ship starts at the top of the screen and you have to make your way carefully to the bottom before starting your attack?