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On March 1, 2017, YandereDev announced a partnership with tinyBuild that would help him polish, promote, and publish the game. YandereDev regularly releases test builds of the game for debugging purposes. He first pitched the idea on 4chan in 2014, and after receiving positive feedback, decided to begin development.
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Yandere Simulator is developed by YandereDev, a freelance game developer identified as Alex and based in Temecula, California.
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1980s Mode features VHS effects and a new complete soundtrack in order to differentiate it from the main story. The developer has stated that this mode was created to test the games various systems. This mode is a complete story mode that follows Ayano Aishi's mother, Ryoba Aishi, and follows the same storyline as the main story. 1980s ModeĪ prequel mode, named "1980s mode" was released in October 2021. In 2020, the game's first official demo was released along with Ayano's first rival, Osana Najimi. The player has the ability to kidnap, torture, poison, electrocute, matchmake, befriend, betray, and drown rivals, befriend other schoolgirls, play small mini games, access a street where the player can earn money by playing a maid cafe minigame, spend money at shops to buy different types of items, and more. Over the course of ten weeks, a different girl will fall in love with Taro, becoming a target for Ayano to eliminate. The player controls Ayano Aishi (nicknamed Yandere-chan), an apathetic Japanese high school girl who has developed a crush on Taro Yamada, a fellow student often referred to as " Senpai".
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Performing murder results in loss of sanity, making Yandere-chan look increasingly disturbed and unstable, with the game's graphics and background music also reflecting the change. Yandere-chan (Ayano Aishi) with high sanity (above) and low sanity (below).
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