Ahhhh, thanks for the info...also just tried to gen a map with 10,000 years of history..but it only went to year 300, does this mean it didn't do it or the 10k went by in different epochs that I didn't see?>
A world with a history of 10.000 years? Thats genius! (although i have no idea if its actually possible)
The thing is that all megabeasts will have died long before that and megabeast do make the game a whole lotta fun, also the generation of a world ends when a certain percent (i think default is 80%) of them megabeasts died, thats default but you can change that when "generating a new world with parameters" and then typing "e". (will probably take you a while figuring out how every parameter effects the generation of a world though, likely with a lot of endless rejects after altering a parameter too much for example).
I also wouldn't advice genning a medium or bigger sized world with a 10.000 year history span, that will likely take forever (in my case, it will likely take 1:1 time cause my computer sucks
). I don't even know wether much would happen for the last 9000 of those 10.000 years. In any case, gonna try genning a small sized world with such a history, i'm affraid of entering legends thereafter though, lol.