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Chet Faliszek (born 1965) is an American videogame writer and formerly one of the main writers for the Valve Corporation along with Erik Wolpaw and Marc Laidlaw before their departure from Valve. He has worked together with his co-writers in order to create the storylines for the Half-Life and Portal series, along with having personally written the story for Left 4 Dead. Faliszek was also the creator of the Old Man Murray website with Wolpaw, which was shut down in 2002. In May 2017, Faliszek announced he was leaving Valve, "want to change things up", but did not state what his future plans were.