1. Language. Each nation has it's own language. Greater civs raise popularity of their language among non-native speakers. If people of enemy city do not know your language they'll never join your civ by free will... Even if the city is deep inside your cultural zone. Also war discontent in war against those who speak the same language is greater.
2. Religion. Two advances and three buildings is not enought for civ4. Each civ has it's religion, it can be changed by ruler or by cultural superior.
2.a. Atheism. (Advance) requires industrial revolution and philosophy. Effect: scientific buildings raise happiness.
3. Terrorism. Destroys buildings and causes discontent in Democratic/Republican countries.
4. Chemical biological weapons. No comment
5. Normal hit points bar!
5. a. How can pikemen destroy an enemy tank?
5. b. The same with trireme and battleship.
6. Defence lines. Fortifications that give better defence than cities, but require upkeep. Minefields. Zone of control.
....
7. Allied victory.
7. a. Map cell can contain units of different nations.
7. b. Countries with the same language, religion and govt. type tend to join (dominato gains control on bpth). Also they can form unions. In this case you rule your country only half of turns or something of this kind.
8. Trade - Limited amount of resources. Patents.
2bcontinued
