I think your idea of a before flood world is sweet. It is a good theme for RPGs because you can tie it in with the real world. The idea of a civilization before time, be it Atlantis or whatever else, gives the author alot of freedom. I liked the dinosaurs with people idea, although there is no imperical evidence to support this, alot of christians will tell you that we simply haven't found the skeletons yet lol. Good argument, if there was a catastrophic flood all of the remains could have been washed anywhere.

Though I am not a christian, I will pimp this site because I am interested in the archaeology aspect of it.

Link

Here's an example I thought up:

What do you know about how a nuclear reactor works? If this sort of technology was in the hands of a few skilled cultures that were wiped out by one thing or another (e.g. flood, meteor), and you and a few others were the only survivors, what could you tell the world about this technology? Likely almost nothing, exept that your people had an advanced energy source that had the power to destroy the world. You might be able to say that it uses radioactive metals like cobalt and uranium but the specifics will be lost. Sound familiar? Hundreds of years pass and your story was written down in books and becomes myth. Although no specifics are given, rumors of an advanced civilization continue.

If the entire world flooded, you would no longer have a reference point for anything. You would no longer be able to locate where anything was without using an advanced method. You would be completely lost even if you are feet from where your home and would have no way to relate directions to anyone else.

Thank you, I'll be here all week.