Call of Duty campaigns tend to place a lot of stock in their ending. While the whole campaign is incredibly important, it's usually a Call of Duty's ending that can make or break the entire experience, either being the perfect final action set piece to a rollercoaster of a high-octane campaign or being a lackluster mess that ends up letting down everything that came before it. Call of Duty: Modern Warfare 3's ending kind of sits somewhere in the middle.