3-D Asteroids

Although this prototype is called 3-D Asteroids, the game itself is exactly the same as the released game (3-D Asteroids was the original name).  

Interestingly there is hidden text inside the rom code that says:

"IF YOU CAN READ THIS YOU'RE TOO CLOSE. GCC© 1984"

 While the final release simply says:

"TOO CLOSE. GCC© 1984"

This is most likely due to the addition of some code tweak or encryption header which increased the file size and truncated the end of the code.