Black: level 4

Really, really fun. The only problem is that it took me one hour and twenty-eight minutes to work my way through it, and because of the retarded checkpoint system I had to do it all in one go. But there were some really good parts - fighting through the factory complex with cover from a sniper (who took out more than their fair share of terrorists), destroying machinery, and shooting large concrete cylinders which rolled down a hill and crushed enemies as they went.