Calipso (c) 1982 Stern Electronics.
You play a diver who is trying to get a treasure. Hold Fire and push in the direction you want to shoot, but you will be unable to move while doing this. Shoot the sea animals and the other player. Try to get the treasure at the bottom and return it to the boat at the top without getting attacked by sea creatures -- all before your air runs out.

>>> TECHNICAL DETAILS
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Main CPU : Z80 (@ 3.072 Mhz)
Sound CPU : Z80 (@ 1.78975 Mhz)
Sound Chips : (2x) AY8910 (@ 1.78975 Mhz)
Screen orientation : Vertical
Video resolution : 224 x 256 pixels
Screen refresh : 60.61 Hz
Palette Colors : 99
Players : 2
Control : 8-way joystick
Buttons : 1

>>> TRIVIA
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Licensed to Tago Electronics for manufacture and distribution.

>>> OTHER GAME RESOURCES
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Game's rom.