There were a decent number of Apollo released games. Lochjaw is the rarer named version of Shark Attack. There is a monogrammed version of Spacechase that is extremely rare, and can only be found by firing up the game. There is a cartridge variation for the GAMES BY APOLLO molded on the back. Where “GAMES BY” is .85” long and “APOLLO” is 1.6” long, this is considered small molded letters. “GAMES BY” is 1” long and “APOLLO” is 1.8” long, this is considered large molded letters. There is also a variation on the 2 posts that go into the Atari unit. A notched post has a semi-circular notch in it, and a square post is perfect with no notch in it. See "General Apollo Variations" link below.