Mechanically, "It Came From the Desert" can be considered real-time. Waiting, sleeping (at home or in a hospital bed) and driving around consumes time. As it turns out, the player has a fixed amount of in-game days (15 days, ending with June 15) to succeed. If Dr. Bradley fails by this date, the ants will mate and spread, which results in a gloomy ending. To reach a good ending, the player must locate the ant colony and kill the queen ant.