Civ4 BtS is the best version of Civilization ever made. Civ5 and 6 don't come even close. Build your empire from the ground up to the stars, fighting, trading, lying, outsmart or rule all your opponents. With my mod TyrMegMa40 I expanded the game on the next level, playing now on a 6 times bigger random map, with 4 times slower time and with 34 civilizations at once. My mod have no fancy graphics or unbalanced units, is just the default Civ4 BtS but a lot bigger! (search for TyrMegMa40 on the net or on my blog).

Thanks! I found it here: https://forums.civfanatics.com/threads/tyrmegma40-mod-mega-marathon-with-34-civs.662336/

I've downloaded and been playing it. I've already had 3 civilizations fall in the first 100 turns.

So what does this bear in comparioson to Caveman2Cosmos?

Yes, this happen because from 34 civs, some fall early. The beauty of it is that they will be back as colonies that get their independence later in the game. So, you will eventually get to play with 34+ civs. Only much patience and love for Civ is needed. :) I never played Caveman2Cosmos so I wouldn't know.