Attack of the Mutant Camels

The premise is pretty much in the bizarre title of the game. Giant mutant camels are advancing towards you planetary base and you have to destroy them via your little spaceship. The game is essentially a side-scrolling shooter with the one exception that the game screen advancement is not tied to your spaceship, but the slow, steady and deadly advance of the giant camel(s). As you shoot the camels, they change colour, which indicateds their damage status.