Information: - King's Quest is a graphic adventure game series created by the American software company Sierra Entertainment. It is widely considered a classic series from the golden era of adventure games. Following the success of its first installments, the series was primarily responsible for building the reputation of Sierra. Roberta Williams, co-founder and former co-owner of Sierra, designed all of the "King's Quest" games until the series' reboot in 2015. - Roberta Williams (born February 16, 1953) is an American video game designer, writer, and a co-founder of Sierra On-Line (later known as Sierra Entertainment), who developed her first game while living in Simi Valley, California. She is most famous for her pioneering work in the field of graphic adventure games with titles such as "Mystery House", the "King's Quest" series, and "Phantasmagoria". She is married to Ken Williams and retired from her career in 1999. Roberta Williams is one of the most influential PC game designers of the 1980s and 1990s, and has been credited with creating the graphic adventure genre. - Mystery House is an adventure game released by On - Line Systems in 1980 . It was designed , written and illustrated by Roberta Williams and programmed by Ken Williams for the Apple II. Mystery House is the first graphical adventure game and the first game produced by On - Line Systems , the company which would evolve into Sierra On - Line . - Sierra Entertainment (previously Sierra On-Line, commonly referred to as Sierra) is an American publisher founded in 1979 as On-Line Systems by Ken and Roberta Williams. Based in Oakhurst, California and later in Fresno, California, the division is now owned by Activision, a subsidiary of Activision Blizzard. What is the relationship between 'mystery house' and 'sierra entertainment'?
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developer