Hey guys, I've never used this forum before, but I just decided to refresh myself on the COD Zombies storyline and thought of a few possibilities for the story.
First off, one of the most basic facts is that the Zombies attack the players. This is said for any and all game modes, and may seem silly to note. But let's remember that this is because Samantha has been controlling them to get to Richtofen for her father's revenge. As such, Sam could have caused some sort of radius to turn people to zombies around the area which the original characters are in. Theoretically, this could mean that certain areas of the world are not destroyed. As far as it's known (up to and not including TranZit), only the areas in which Dempsey, Takeo, Nikolai and Richtofen have been to are damaged or worse. There are no other areas which have been affected, other than those hit by the rockets launched by Richtofen. These areas' destruction is insignificant, since it is said in the gameplay that Richtofen's calculations were hasty and sloppily planned, and thus would affect a larger area than he wanted.
Also, it is said several times throughout the early storyline that Maxis worked with Takeo, Nikolai, and Dempsey, and hints that they are super-soldiers (as is evident by their fighting abilities). This could be the reason why they are not affected by Sam's or Richtofen's control, or any sort of 'disease' the zombies may spread.
Maxis also told the O3 that he had a back-up plan to stop Richtofen. Since Marlton, Russman, Misty and Samuel all survived the rockets and nearly global infection, wouldn't it make sense that they were also at least partially super-soldiers? Given that this is true and that Richtofen, being as smart and powerful as he is at the end of Moon, found out or knew of Maxis' back-up plan, it would also make sense that Richtofen would be able to pin-point where to place zombie outbreaks/attacks (or to tell the zombies where to go -- not quite sure how the control works).
This also would explain why Richtofen would even bother trying to persuade Samuel into joining the zombies in the opening cutscene of Die Rise. Being a man of endless power, he would find no need in talking a single person into becoming a zombie. If he knows that Samuel is part of a plot against him, or even more, a part of a group of four people (all of which are super soldiers) against him, killing or turning him would be extremely valuable.
That is one part to it.
Now, continuing from that information...
Let's say that Maxis' goal is to teleport himself from the Aether. Sure, this may seem selfish for a man like Maxis, who cares for Samantha, but this is his back-up plan. Once this is done, the N4 characters can die off since they do not play a part any more. So let's say Maxis is teleported to the O4 characters. Now we have 5, including Richtofen with Sam's soul. They're re-united, despite Samantha being in a different body. The last thing to do at this point is to take Richtofen out of control. I believe that either way this progresses, it will be done, but after that, one of two things will happen:
Richtofen will return to his body, and:
-Richtofen will kill Maxis. This will result in the O4 killing off Sam-controlled Zombies.
-Maxis will kill Richtofen. This will result in Sam taking control again. In this scenario, I believe that Samantha will go crazy as Richtofen did when he touched the MPD. Maxis and the O3 will have to find another way to take control away from Sam as Richtofen once did, this time with Maxis in place of Richtofen.
I thought this was a pretty cool theory which is supported in some areas, albeit I recognize that most of it is just a guess. I originally had more thought out, but it's easy to forget when writing this much. What do you guys think? :D