There is an Atlantis II for Atari 2600 auction on ebay. The game is already selling for $230 and is sure to go much higher.
Atlantis II is one of the rarest games for the Atari 2600. Not quite as rare as Air Raid but some collectors think there are fewer than 25 of these ever made.
Atlantis II History
The game was made by Imagic and is a sequel to the original Atlantis for 2600, but was made specifically for a contest to determine the top four players in the world.
Gamers would send in their high scores from the original Atlantis and the top scores would be flown to Bermuda for the Great Defend Atlantis Shoot-Off on November 14, 1982. Lots of players sent in their scores and more than four even maxed out the score on Atlantis. Imagic couldn't determine a winner the way they originally planned so they made Atlantis II.
Atlantis II harder, faster, and lower scoring so they could determine the winner. The top competitors were mailed the game along with some other prizes and told to mail in their scores after two days of playing. The exact number of games mailed has never been confirmed but estimates range from 250 to 25.
Thank you AtariAge for your information on Atlantis II . You can read a much more thorough history on their site.
Atlantis II vs Atlantis 1 - How to Tell Them Apart
The Atlantis II and original Atlantis cartridges look the exact same on the outside so telling them apart isn't like normal games. It requires a scale or seeing actual game play footage.
Method 1: Game Weight
Atlantis II weights less than Atlantis I. According to this Youtube video Atlantis II should weight about 5.55 grams. Every Atari 2600 collector should go put their Atlantis cartridge on the scale and see if how much it weights. That one test might be worth hundreds of dollars.
Method 2: Score Font
The other difference between Atlantis and Atlantis II is the font. The font on the score for Atlantis is a serif font (fancy lines on the edges of the letters) while Atlantis II was a sans-serif font (no fancy design). Who would have thought typography would come in handy in video game collecting?