Zoo Tycoon is a business simulation game developed by Blue Fang Games and released by Microsoft. Although first released for Microsoft Windows and Macintosh in 2001, it was ported to the Nintendo DS in 2005. It was followed by two expansion packs, Dinosaur Digs and Marine Mania, which were released in 2002, as well as a sequel, Zoo Tycoon 2, released in 2004. Gameplay The goal of Zoo Tycoon is to create a thriving zoo by building exhibits to accommodate animals and keeping the guests and animals happy. Exhibit-building is one of the primary goals of Zoo Tycoon. To keep the guests and animals happy, exhibits should be suitable to the animal; for example, a lion is best suited to a savannah environment. Choices in terrain, foliage, rocks, shelters, fences, toys and the presence of zookeepers all contribute to the suitability of an exhibit and the happiness of the animal. Guest happiness is dependent on animal choice, animal happiness, buildings, and scenery. Buildings include bathrooms, restaurants and food stands, shops, reptile houses, aviaries, and entertainment buildings such as movie theaters. Scenery involves aesthetics that raise guest happiness slightly, such as topiary art, light posts, and benches. Keeping both animal and guest happiness high allows the player to gain monetary awards and maintain a steady income. To help manage the expanding zoo, players can employ maintenance workers, zookeepers and tour guides. If the animals escape from their enclosures, they can attack and possibly kill guests and employees. There are three modes in Zoo Tycoon: Tutorial, Scenario, and Freeform. Tutorial teaches the player how to build exhibits and keep guests happy. Scenario mode has the player complete a series of objectives under restrictions. These objectives may include achieving a certain guest and animal happiness, achieving a certain exhibit suitability, displaying a certain number of animals, or breeding a certain animal. Freeform allows the player to choose the amount of money and the map with which they start. They are presented with an open lot and a limited selection of animals, buildings, and scenery available for purchase. As the game progresses, more animals and items become playable. Additional animals and items may be researched, where money is invested to make them playable. Development Blue Fang Games originally considered making a simulation game where the player would manage an airport, before the idea was dismissed by CEO Hank Howie, citing that compared to places