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This incredible war FPS, from the same makers of Operation Flashpoint, has something amazing you might not notice at first:

It runs so realistically nice because it’s actually running hundreds of AI controlled characters at the same time.
Opposite to mosts FPSs, the bottleneck on this game isn’t the graphics card, but processor power and speed, since it has to run this many AIs at the same time.
ArmA II was recently released by Bohemia Interactive, a team formed by ex-Codemasters employees responsible for Operation Flashpoint.

Source: Kotaku