Destination Atlantis

Destination Atlantis was a competition held by Imagic, a video game developer, in 1982. Imagic were the creators of Atlantis for the Atari 2600.

Imagic invited players of Atlantis to take pictures of their high scores on their television screens and mail them to the company. Those who had the highest scores were then rewarded with a copy of Atlantis II. The latter game, rather than being a mass-produced sequel to Atlantis, was a special edition of the original Atlantis, featuring faster enemy ships which were worth fewer points. The concept behind this was to create a more difficult game that would "determine the true champion".

As very few cartridges were created, Atlantis II is now a rare and highly-valued collectors item. Prices as of 2010 can reach 6000 USD.

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Wikipedia