Crash Dive is the shooter 20th Century Fox Games published in 1983 for the Atari 2600: the player controls the Sea Hunter, "the world's only flying submarine," and has to sink ships, planes, giant sharks, and a whole hostile sea fauna while managing fuel by returning to refuel at the mothership Sea View. The screen splits into two planes — below and above water — with different speed and risk rules in each, a more sophisticated design idea than usual for the console's catalog.
It's a good example of how, by 1983, third-party studios were already squeezing the 2600 with increasingly ambitious ideas, right as the market was starting to crack. For today's player it retains that charm of a wacky premise resolved with technical seriousness.

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