Horizon Zero Dawn is an action role-playing video game developed by Guerrilla Games and published by Sony Interactive Entertainment for the PlayStation 4. The game was released worldwide in 2017.The plot revolves around Aloy, a hunter and archer living in a world overrun by robots. Having been outcast her whole life, she sets out to discover the dangers that kept her sheltered. The character makes use of ranged, melee weapons and stealth tactics to combat the mechanised creatures, whose remains can also be looted for resources. A skill tree facilitates gameplay improvements. The game features an open world environment for Aloy to explore, divided into tribes that hold side quests to undertake, while the main story guides her throughout the whole world. Development began in 2011, with game director Mathijs de Jonge considering it \"the most risky\" idea of those that were pitched at the time. The concept explores the contrast between the beauty and danger of the game\'s setting. Guerrilla Games emphasises trial and error as the basis for playing the game, choosing not to implement a tutorial.The game engine, Decima, was previously engineered for Killzone Shadow Fall and altered for Horizon Zero Dawn, the first new intellectual property (IP) developed by Guerrilla Games since Killzone in 2004, and also the studio\'s first attempt at developing a role-playing game.