if you are looking for a long campaign that plays fast, id recommend Rainbow 6 Vegas.
if you are looking for a shooter that makes you feel as if you are actually in special forces (like rapelling down the side of a building, infiltrating a building, fast-roping into an area), R6V is for you. the AI is exellent, both enemy and team mates. the enemy tries to flank you as much as possible, and are pretty good shots. also, with the rebounding health meter, you dont have to play as carefully as you used to do, but still, one shot can easily take you down, so you gotta be careful.
the cover system in the game makes other games look bad, for the system for covering is so great, i feel like ehenver i pass by a low wall or go to a corner in real life, i want to duck down and look around the corner for terrorists.
the story, while the standard run of the mill terrorist-got-a-big-bomb-and-wants-to-kill-people, you dont think of that when you play it. the action is very intense. and its light on the specs.
the game looks amazing, but needs anti-aliasing. also, its an old game, from 2006, so dont expect crysis-like graphics. but i will say, theres something about fighting in a casino that is just AWESOME.
COD4's campaign is good, but short. its main strength is its MP. thats why i say R6V.
and its really cheap. i got it for $10.
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