After hearing about more treasure on a nearby coast, you hop in your trusty submarine and take off.
The treasures are still located in caverns so you'll have to be careful in 25 levels of undersea action!
Take control of your submarine as you travel through the caverns in search of the exit. 
Oh no! You seem to have attracted the attention of one of the local denizens - a giant octopus!
He pursues you from level to level. Your torpedo is too small to kill the octopus, but it will drive him off for a short while.
Can you make your way to safety? Or will you find your final resting place under the sea? 
GOSUB 2 is the sequel to the first Atari 2600 homebrew game that Chris Read programmed. (GOSUB)
He later went on to create Alien Greed, Alien Greed 2, Alien Greed 3, Alien Greed 4, Alien Greed 5, and Alien Greed 6.  There's lots to explore in this 8K videogame cartridge for the Atari 2600. 

GOSUB 2  is compatible with NTSC systems.
Includes game cartridge and a printed full-color instruction card.