All of the game's major systems have been improved from previous games. For example, it is no longer possible to switch the build points from one project to another. So, players can no longer take advantage of the exploit where they would build a Wonder for many turns, then switch projects so that all those points can be used to instantly build another project. Additionally, the combat system has been updated so that all units are measured by power. More modern units are distinctly more powerful than primitive ones, and units will become more powerful with upgrades and experience. Also, the technology tree has been revamped. Technology is no longer dependent on the era. So, the player is free to follow specific technology paths, and go find research technologies they might have missed. All discoveries are voiced by Leonard Nemoy, whose voice adds distinctive charm to the game, making it all the more enjoyable.

Lastly, the computer intelligence and diplomatic system has also received an upgrade. You can still talk with different leaders and exchange money, technology, and goods, but the most important option comes from the open borders policy. Unless open borders are granted, no nation may pass into another's territory unless they are declaring war. This is a great change for players who like to focus on infrastructure and scientific development. In previous games, units were free to travel wherever they wanted, and the only way to get them to stay out was to do a lot of complaining. This way, there is less chance of being caught in an ambush. Lock off your borders too often or refuse too many favors, and the computer will remember them, making future relations and deals all the more difficult. The computer players will also make much more reasonable demands and won't be easily bought off with tiny bribes.

Civilization IV plays remarkably fast for turn-based strategy game. Discoveries, developments, and eras will seem to fly by. There are three speeds: normal (which is still pretty fast), quick speed (to make things even faster!), and epic speed for those who enjoy slow building. At normal speed, conquering the world may only take a few hours. The great thing about the increased pace is that it makes the multiplayer component much more viable, and the whole spread is available here. There is LAN, hotseat, internet, and play by e-mail.

The soundtrack to Civ 4 is relaxing, although (with the exception of a few tracks) it has a tendency to easily fall into the background. The music doesn't seem to have any specific ties to nations, although the opening track could have easily walked off the set of The Lion King. What is really intriguing is that units respond in the native language or their nation's origin, showing the strong attention to detail that the Civilization series is famous for. To the disappointment of some, minor touches such as having your leader's clothes change in accordance to the time period, have been left out. Also, the Civopedia has been scaled down to a quotation instead of explaining the significance of a particular discovery. However, players might forgive this when they see the beautifully animated units and when they zoom in to extremely close-up views of their cities. Civilization remains as engrossing as ever.

Civilization IV is perhaps the best Civilization game yet, making it the best in a line of great games. Fans of the series probably already own the game and don't have to read this review. For the rest of you, go get this game. It is superb on almost every level, and firmly captures the Civilization addiction all over again. So, give in and conquer the world one turn at a time all over again!