Reviewing an expansion pack is tricky. Rarely does one radically change the way the game is played and it's usually just more of the same – expansions are all about more "stuff" so it's hard to really determine if they're worth buying. Civilization IV: Warlords is loaded with goodies, from new races and technologies to game-altering scenarios that bend the rules of play and make the game seem as fresh as ever.

But is that worth another 30 bones?

It's a difficult question to answer because 30 dollars to you may not mean the same as 30 dollars to me. It comes down to this: if you're a Civ IV freak and have the cash to spend then this is a no-brainer purchase. It's a very good addition to the series.

Warlords brings new faces into the fray: the Carthaginians, Celts, Koreans, Ottomans, Vikings, and the Zulus are the expansion's new factions and of course with each new race come new leaders like the infamous Hannibal of Carthage and Shaka of the Zulus and old races get new leaders as well such as Stalin in Russia and Augustus Caesar in Rome. Each race also gets unique units (and may now use a Trebuchet and Trireme) and personally stylized music. (The sound effects in the add-on remain stellar throughout).

In addition to the leaders and units each race (new and old) now gets a unique building which helps to further differentiate each faction. The buildings vary from the serious (like the German Assembly Plant) to the stylish (the American Shopping Mall, for instance) but the idea is a great one – by continuing to add more things to each race it only helps make them stand out a bit more. What makes it such a great design achievement, though, is that it doesn't break game balance, which is what makes the folks at Firaxis so darned good at this.

The other big addition is what the name of the expansion is based on – the Warlord unit. This adds a needed military "Great Person" to the design in addition to the artists and scientists from the original game. Seriously, if you're gong to add Zulus and Vikings and Carthaginians – you need to focus on bloodletting. Warlords can speed up military construction time or lead a stack into battle, providing additional bonuses to the units. The Warlord can also be used on a city which provides +2 experience for any unit built there. Not bad.

There are other tweaks such as a handful of new Wonders and the addition of Vassal States, but that's basically it for "new stuff." In fact the core game feels and plays exactly as before. Not that this is a bad thing as Civ: IV is easily one of the best games released in the past five years, but the new stuff isn't going to wow you over by itself, particularly not at $30.

However, the heart and soul of the add-on is in the new scenarios. The scenarios do a great job of not playing it safe – these are not standard games but rather game altering designs. Take the Chinese Unification scenario – in it, you need to bring together the feuding Chinese families by creating bloodlines and arranging marriages. How's that for a different spin? The scenarios have tweaked tech trees and adjusted rule sets, making them a true joy to play. You can even play a scenario as the Barbarians! The classic Omens scenario pits you as either the French or British as you attempt to colonize North America in the 18th century, spreading religion along the way. You need to convert three fourths of the map by the end game. The twist is that the Divine Spirit shows up on occasion to literally flame the faction that is in last place. The Omens does a good job of showing just how powerful the Civ IV editor really is. Other notable scenarios include The Rise of Rome, Genghis Khan,. The Age of the Vikings, The Peloponnesian War and Alexander The Great.

As good as the scenarios are, it should be noted that you can download a whole slew of well-made user-made mods online – scenarios that take place in space, or in a fantasy themed universe. The plus side here is that the ones in the game are all professionally designed and the quality is not in question – still, some of the user-made content is just as solid...and it's free.

In the end, it all comes back to value. This is a very well made expansion pack – everything that it adds helps the game, even if it's in small doses, while the new scenarios are sure to add hour upon hour of enjoyment…even if it's priced around what it costs for a brand new game. Prepare to get addicted all over again. - William Abner