User blog comment:Argorrath/Treyarch posts a message of zombies; possibly hinting to a DLC 4/@comment-5134053-20130801051305/@comment-9010268-20130802203512

1: He was just stating a theory like most people here.

2: Theories are things that have little solid evidence behind them, so seeing as how it is just a theory no proof outside these notes is needed.

3: ;)