complete specific missions in order to win the game, such as racing, tailing, couriering, robbing, stealing, shooting, assassinating, and driving to specific checkpoints. There may be multiple ways to complete these missions as the game environment is designed to facilitate shortcuts, experimentation, and creative ways to kill enemies. Completing a core mission will unlock further missions and advance the storyline, and if the player fails a mission they will be able to resume the game from before the mission began. In addition, these games usually offer optional side missions, which allow players to gain other rewards. These side missions improve the game's replay value. These games are also known for incorporating numerous minigames into the game world, such as circuit races. Ultimately, this allows the player to follow or ignore the game's storyline as they see fit. History Origin Open world, 3D action-adventure games existed for years prior to the release of any similar game from the Scottish developer DMA Design. Mercenary (1985) has been described as a major ancestor to the Grand Theft Auto series, because it featured an open world which the player could explore freely. Turbo Esprit, the first free-roaming driving game, featured an explorable city with traffic, pedestrians and working traffic lights and has been cited as a major influence on the Grand Theft Auto series.Charlie Brooker's Gameswipe, BBC Television, 2009. "Grand Theft Auto ... directly inspried by the pioneering Spectrum game Turbo Esprit" The Terminator, released in 1991, was a free-form, open world game that set its action in a modern-day city that extended for miles, and included the ability to fire at civilians and steal cars. This game was also among the first American-developed games to feature these elements.Hunter (1991) has been described as the first sandbox game featuring full 3D, third-person graphics, thus making it an important precursor to the Grand Theft Auto series. The game consisted of a large, open world in which there were numerous possibilities to complete different missions. The character could travel on foot, or steal different vehicles such as cars, tanks, or even bicycles, boats, helicopters and hovercraft. Moreover, Hunter also had many unique features such as day and night lighting, fuel modelling, a log book, aerial observation units, tank traps, land mines and computer-controlled rocket batteries and tracer guns. It was also possible to ride a bicycle, swim, windsurf or even make a parachute jump from a