Last year's Stronghold was a slightly uneven combination of city builder and real-time strategy game, with an emphasis on siege warfare. It had the distinction of being the only castle simulation from a major publisher since Interplay released Quicksilver's Castles II in 1992. Aspiring warlords could forgive Stronghold's shortcomings, since the original game gave them the opportunity to build and raze walls, pillage countrysides, and launch cattle from catapults. Firefly Studios has now polished up its old game nicely and has sent it on a long road trip into the Crusades.

The new watchtower can fire farther.

Stronghold: Crusader is the stand-alone successor to Stronghold, meaning you don't need the original Stronghold to play it. It takes Stronghold out of Europe and into the Holy Lands, giving it a tighter focus and a more exotic flavor. The economic missions that had you racing against the clock to fulfill contrived objectives have been removed from the game. Instead, Stronghold: Crusader places more emphasis on the fine art of defending or storming a castle. After all, isn't this what you want when you pick up a box with a knight standing in front of a castle? When players first looked at the box for the original Stronghold, they probably wouldn't have guessed that they'd be spending their time accumulating 500 units of cheese.

Indeed, the original Stronghold divided its single-player missions into two types: military and economic, though the latter, which generally involved raising crops and stockpiling resources, wasn't as popular as the military missions. It also had a single-player skirmish mode and head-to-head multiplayer. But Stronghold: Crusader presents you with many more options. For instance, you can play skirmish games against AI opponents on a number of different maps, even in multiplayer. Some are completely even playing fields, while some feature interesting balance dilemmas, giving advantages and disadvantages to each player. The skirmish maps can be played against your choice of AI opponents or in multiplayer games.

However, players who are new to Stronghold's economic model, which actually folds elegantly into its combat model without upstaging it, will likely want to start out by playing with the castle-builder option. This is a sandbox mode that, like in the original game, lets you learn the unique features of Crusader's new desert maps without having to worry about fielding an army to defend against attacks.

But the centerpiece of the single-player game is the "crusader trail," which presents a series of 50 battles, each more difficult than the last. As you play, your performance determines the ongoing date, which serves as your score. You can go backward to replay old missions, and if you do better, the date will roll back. Although this doesn't have much impact on the actual missions, it's an interesting alternative to tracking a score based on points.

Farmland is hard to come by in the desert.

Unlike the missions in Stronghold's military campaign, most of the missions in the crusader trail let you build you own castle. This makes it more like a series of skirmishes than the original game's linear sequence of canned scenarios with prebuilt castles. The crusader trail missions do a good job of incorporating specific units and strategies, and you will gradually improve your skills as it ramps up the difficulty level. In addition to a basic tutorial, there are four historical campaigns, in which each chapter highlights specific game elements, such as which units are best suited for which purposes, how to manage your taxes, and the differences between various crops. Each mission in these campaigns is like a puzzle with a historical context, which, once solved, will teach you to play better. Stronghold: Crusader has numerous options to introduce new players to the game as well as plenty of challenges for veterans of the original Stronghold.

Stronghold: Crusader makes some important changes to the dynamics of the original game. Most significant is the addition of seven new Arabian mercenary units, some fairly redundant (Arabian bows are just weaker archers), some potentially overpowered (the horse archers are a potent combination of speed and ranged attack), and some adding unique game dynamics (assassins can secretly open gate towers to let your units into an enemy's castle). The new units are all hired from the mercenary camp, which can be built cheaply as soon as you start building your castle. To recruit them, you don't have to harvest resources, construct weapons, and accumulate an arsenal in your armory, like you have to with their European counterparts. Instead, just fork over some gold, and these new Arabian units will show up.