Shark! Shark!

Shark! Shark! is an Intellivision game originally designed by Don Daglow, and with additional design and programming by Ji-Wen Tsao, one of the first female game programmers in the history of video games. The player is a fish who must eat smaller fish in order to gain points and extra lives while avoiding enemies such as larger fish, sharks, jellyfish, lobsters and crabs. After eating a certain number of fish, the player's fish grows in size and is thus able to eat a larger selection of fish. However, while the larger fish becomes a bit faster, he is less agile than the small fish and has a harder time avoiding enemies. As the game player continues to amass points by eating smaller fish, or killing the shark with multiple bites to his tail, the shark becomes increasingly faster, and eventually, invulnerable jellyfish are added to the mix which makes the game considerably more difficult. At 100,000 points, the shark becomes super fast, and even the best players' fish die at alarming rates, often finding themselves slamming headlong into jellyfish or larger fish in their mad flight away from the deadly shark.

Shark! Shark! was originally considered by Mattel to be a cute game for kids and unlikely to make strong inroads into the gaming community. However, the market caught Mattel unprepared when it fully embraced the game as a sorely needed Intellivision original. The game's popularity skyrocketed, forcing Mattel to quickly manufacture another batch of cartridges. The original cartridge run was only 5,600 units.