Atlantis Underwater Tycoon

Atlantis Underwater Tycoon, also called Deep Sea Tycoon worldwide and Aquatic Tycoon in France, is a business simulation video game in which you must create an underwater civilization, and become a tycoon. It was developed and published by Activision Value, and released on April 15, 2003 for Microsoft Windows on PC.

Gameplay
The player starts with a home base, and expands from there. As the city expands, a wider range of buildings and residents become available. When these new items are placed, they bring in more tourists and residents with money, and this unlocks new buildings.

As well as having to balance the economic aspects of the game, the player must contend with attacks from enemy submarines.