I am part of the largest decade in civfanatics, the 80s. I've been playing civilization since it came out on SNES as civilization and passed it on the hardest levels. However, civilization 2 added wonders, more neat things and a new challenge with more difficult ais. I missed civilization 3 but got to civilization 4 and bts which also became very challenging in comparison to the basic civilization so I had to learn how to win in higher difficulties. Civilization 5 bnw also is challenging because of all the new things that are different from bts.