User blog comment:Damac1214/Call of Duty: Advanced Warfare DLC Comes First to Xbox Live/@comment-1263839-20140503115422/@comment-1263839-20140503161312

World at War introduced Zombies so:

Infinity Ward's attempts at grabbing Zombie's fame:
 * MW2 - Spec Ops
 * MW3 - Survival Mode AND Spec Ops
 * Ghosts - Extinction

If SHG makes an alternative Solo but also Co-Op mode (which they definitely will because Zombies says they have to), then it will be the fourth attempt.