1up try their hands on Valve's Left 4 Dead.
"Co-op is vital in L4D, just like in Epic's Gears of War, but the way the drama unfolds is entirely different. In Gears of War, during the campaign's branching moments, you and your partners separate -- if one dies, you all fail. In L4D when one of your team members goes down, the round doesn't end; it just gets that much harder. The Tank we brought to its knees earlier would've stomped, eaten and torn us apart if we were anything other than four-people strong."