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Valve has stressed that Overkill Software’s Payday: The Heist – No Mercy won’t be a prequel to Left 4 Dead. Overkill had labelled their now-pulled teaser trailer of the game with: “Have you ever wondered how the Left 4 Dead series began? It started with a heist!” The video depicted a mission that is located within Left 4 Dead’s Mercy Hospital. Valve’s Chet Faliszek, however, told Kotaku: “This is a 100 per cent Overkill made mission for Payday: The Heist simply set in No Mercy hospital from the Left 4 Dead series. It is not telling the origins of the Infection and is not canon.” 
Although details are scarce, Overkill announced a collaboration with Valve last month regarding a crossover involving Left 4 Dead and Payday. By Zak Islam |