Nothing from, in, or about YuGiOh! is mine.

"Monster stats. Who would have thought?" Asked Mokuba, earning him odd glances from several people. "I hope that was rhetorical, Mokuba," mumbled Yami. "True. From what Yugi's told us, everything you guys end up doing together has something to do with Duel Monsters and the like" Leanna added. Mokuba laughed. "It's true. Perhaps I should ask why nobody thought of it sooner. With our record, it should have obvious from the first."

Seto snorted quietly, and Yami agreed completely. It was almost ridiculous, if you thought about it sometimes. How many times would wanna-be evil dictators could there be that wanted to use Duel Monsters to take over (or destroy, as the case may be) the world? In his experience, too many.

"I recognize these cards," Seto declared to Yugi. The short duelist waited for further comments. "Most of these don't exist- not really. They are custom made, and officially illegal." Nodding his head in understanding, though mildly frustrated that Seto could not just come out with it and decided to be dramatic just then, Yugi made a motion to continue. "I have seen them before. It was from old…allies, I suppose you could say, of Gozeburo. Once again, officially, said alliances never existed. These cards they used as their calling cards."

"Could we skip to the relevant part, please?" a rather annoyed former-Pharaoh asked. Mokuba sighed, knowing that such demands would only annoy Seto more. A dark-glare fight later, with no clear winner, Seto continued speaking.

"They also used the stats as a code. See here? The numbers are slightly off." Yugi 'hmmed' his agreement, trying not to irk any of the egos currently situated in the room. "So do we know what the code actually says?"

"Yes and no. Most of the code is…currently and temporarily unknown. Given more time, I could doubtlessly crack it. I do remember one bit, and it's here, in one of the more recent messages. Right before everyone started getting sick. It's the Ragnarok Signal. Taken from Norse mythology, Ragnarok is the end of Valhalla. In the current situation though, it would appear that it was the sign-"

"the sign to poison the water," Yugi completed.

"And look, you even managed to figure it out without any friendship or 'heart of the cards' speeches" snarked Seto, but it fell rather flat. "When he rescue team finally arrives, Mokuba and I should be able to crack the rest of the code in no time. Hopefully the 'Old Alliance' as they called themselves are as foolish and sure of themselves as I remember. Until then, I'll keep working on the codes in case I can figure anything else out."

Yugi nodded his agreement. "How did you figure out about the Ragnarok Signal bit though?" Yami asked. "As I said, they were foolish and no match for me even back then. It was simple enough, really."

Yugi had gone back to work, doing his best to pretend that this little refuge was not rapidly succumbing to the virus-when the sound of helicopter blades broke through. Trying not to get their hopes up, survivors hesitantly peeked their heads out of the various buildings, straining towards the sky and praying it wasn't another bad thing about to happen-

And the relief was palpable through the camp when the Kaiba Corporation insignia was seen. Yami pretended not to see Seto's smirk as the camp looked on the 'copter as though it were St. George come to save them from the dragon. Yugi noticed Yami pretending and poked him in the side, giving him a sidelong look. Which Yami also ignored.

Seto talked with the pilot as soon as he landed, and for the first time Yami thought that the pressure that had been tight around his chest had eased just the tiniest bit. Please, he thought, let this be the end.

To answer:

It is unclear to me when in the canon this story is supposed to take place. It is obviously post-Battle City due to the reference to the Duel Disk but giving a specific time period would help me understand the thoughts and philosophies of the characters (as their personalities changed through the course of the series).

Another question is Yami's existence outside Yuugi's body. You made it clear that there was a time when Yami was inside Yuugi (therefore assuring me that this story followed the canon for the most part). What isn't clear is how and when he got his own body.

My last question would be where was Yami that he ended up on a plane with Seto and Mokuba?

I understand if you do not wish to answer these questions and simply expect us to immerse ourselves into the setting you have created for your story but I could not help but wonder.

Apologies, I have a way of having things inside my head that don't make it to the outside and confusing readers. This is rather AU, so please forgive me! All of this takes place after the series ends- except I am going with a common Fanon theme that Yugi and Yami were given separate bodies after the duel. Yami was (at least in my head) returning from a dueling competition with Seto. Hope this helps, and once again, I apologize for not making it very clear and not responding sooner. I had intended to update this much earlier than I ended up doing.