please read this tag it's very good
As previously stated there is the addition of new scenarios. Beyond the Sword comes shipped with eleven exciting and creative scenarios. Three really caught my eye. There is a space age game almost similar to that of Galactic Civilizations II, a game set in the far future (with future tech units you can play with in the normal game), and three player created mods that managed to find their way on the CD: Rhye's and Fall, Fall from Heaven, and a WWII: Road to War scenario. They are all great additions and could certainly have been packaged as an expansion pack on their own.
I accidentally stayed up for hours playing this new expansion, you probably will too. I urge any civ fan to go out and give this expansion a shot