Treasure of Atlantis is a Game that the User has loaded into Mainframe.
The Game takes place completely under water. The User is a silver shark submarine, and has fifteen lives in the Game. To win he must find the Lost Treasure of Atlantis. There are several obsticals in the Game to keep the User from finding the treasure. Dozens of Game Sprites fill the Game and are programed to stop the User and some to stop the Mainframe players from getting to the treasure as well. The User must compete against other submarines and merfolk to find the treasure. The first one to the treasure wins, if the User loses all his lives before he reaches the treasure the Mainframer's win
Enzo Matrix, Bob, and Dot Matrix were caught in this Game. Enzo rebooted into a Captain with an eye patch, inside a brightly colored flatfish submarine. Dot and Bob rebooted as mermaids. Their Game characters are telepathic. Dot has a trident for a weapon, it can create a nasty vortex or a piranha mine. Bob can grow spikes from his glove to unleash an electrical blast. They have to stop the User from getting to the lost treasure of Atlantis.
A human looking Game Sprite finds the User first. She unleashes a throwing-star starfish. The small weapon knocks a hole in the side of the User's vessel, but does not disable it. It responds by sending out a depth charge that leaves the Game sprite floating helplessly. Just before the User's torpedoes hit, Enzo swoops by and scoops up the player. Enzo checks his unconcious friend, and she wakes up, hissing and threatening the boy with sharp spines.
Enzo comments on the Game sprite's cool spines. She tells him that they're not poison, just paralyzing. She introduces himself as AndrAIa. Enzo thinks she's just someone he's never seen in Mainframe before. She yells for quiet, then commands Enzo to turn to avoid the wolf eels up ahead. They move into a different tunnel. Enzo regales AndrAIa with tales of being a Guardian. The two youngsters meet up with the User, and quickly take it out with manta rays and sting rays, but have to duck into a side cave as the User is regenerated.
Later, Enzo panicks when he sees Bob and Dot trapped. The User starts moving toward the treasure again. Enzo exclaims how they will all be nullified. AndrAIa doesn't understand what nullified is. He has to explain this concept to AndrAIa, and that's when Enzo realizes she is a Game sprite. There's no way they can be together, she will disappear when the Game Cube leaves, win or lose. "But we can be together," she says, as she pokes him with a paralyzing finger nail and he falls unconcious. AndrAIa removes her back-up, a triangle with the letters "AI" on it, and places it on Enzo's icon. She puts Enzo in a torpedoe and shoots him out of the ship towards the treasure. The unmoving Enzo reaches the treasure before the User and the Game ends.