In other words, rather than have a single hub for all these games, Activision has created two but you can't access Modern Warfare II, Warzone or the DMZ without first accessing the main Call Of Duty HQ app!
From COD HQ, head to the Modern Warfare III section and select the Campaign tile. Even though the game has already launched, we don't want to spoil anything about it. Follow the prompts when starting the Campaign to choose your difficulty setting and then get right to it.
It's very scary, but not that graphic; occasionally a character will get shot or harmed by another, but most of the violence in The Terror comes from nature: dying from a great fall, for example, or being frozen alive.
Terror is usually described as the feeling of dread and anticipation that precedes the horrifying experience. By contrast, horror is the feeling of revulsion that usually follows a frightening sight, sound, or otherwise experience.