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The Refractor Engine is a game engine designed by Stockholm-based studio Refraction Games, first developed for the game Codename Eagle, which was released in November 1999. Refraction Games was bought by Digital Illusions CE, which, working alongside the Refraction Games team, designed and developed the Refractor 2 Engine for the Battlefield series. The following games use the Refractor 2 Engine: Battlefield 1942, Battlefield Vietnam, Battlefield 2, Battlefield 2142 and Battlefield Heroes.