For the title's single-player campaign, the game makers at Swedish developer DICE took a cue from the popular multiplayer mode of 2011's "Battlefield 3, " focusing more on open environments, allowing players tactical freedom and giving them more ways to command squad mates.

NPR: EA Teases Dramatic 'Battlefield 4'

Each participant was told that he or she would compete against an unseen opponent in a 25-trial computer game in which the object was to be the first to respond to a visual cue on the computer screen.

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