Barry Caudill, Civilization IV Senior Producer on Promotions
In Civ III, unit promotions involved rising in level from green to veteran to elite and each level added a hit point and a small combat bonus. For Civ IV, we decided to build on this system and make promotions much more intricate and customizable by allowing players to choose from over 20 different bonus types (many with multiple levels, for a total of over 40 available promotions). The numbers and types of available bonuses differ per unit type and only land and sea military units can acquire them (air units are different).
Here’s how it works: Units can gain experience points in several ways. Successful combat is the primary means (note: you get more points from attacking than you do from defending) and the units must be victorious in a unit-to-unit combat, therefore there are no XPs (experience points) from bombarding fortifications or if the opposing unit withdraws. Units can also gain experience from a Barracks (land units), a Drydock (sea units) or a goody hut. In addition, some wonders, civic choices, and leader traits can give units extra experience or even certain promotions. As you might expect, the first promotion comes rather quickly, while each subsequent promotion requires more XP.
The promotions take on many different forms. Some are simple like Combat (5 levels), which gives progressive strength bonuses with some extra healing at the top levels, or City Raider/City Garrison which gives the unit bonuses only when attacking/defending a city. Others give bonuses against a certain type of unit. For instance, Cover gives a bonus against Archery units and Formation gives a similar bonus against Mounted units, while Shock does the same against melee units. Some promotions give bonuses based on the type of terrain in which the unit resides. If your opponent has a lot of woods or jungle, you might choose Woodsman, or if your opponent is surrounded by hills you might choose Guerilla.
All in all, the new promotion system in Civ IV offers players a plethora of interesting new decisions, excellent customization options, and an extra layer of strategy. That’s how we spell fun at Firaxis Games.
The final aspect of gameplay is for many players also the most important one: combat. If diplomacy fails, or if you're just feeling like kicking some arse, you can declare war on an opponent and take what you want from him/her by force. To do so, you need to build an army of Units and use those to attack enemy Units and Cities, or to pillage his/her Improvements and as such damage his/her economy. But even if you don't want to go to war, you'll still need to build an army: if someone else declares war to you, you'll need to be able to defend yourself. And even if other nations don't declare war, Barbarians might invade you. Posting sentry guards along your borders and fortifying Units inside your Cities to guard them is a wise precaution. When expanding your empire peacefully, you will need to explore the lands around you to find suitable locations to build new Cities, and you'll need to send out Settlers to actually found those Cities (along with escorts to protect them). You need to build Units for these purposes as well. And of course, in order to expand to other continents (either peacefully or aggressively), you will need a navy.
Units in Civilization IV function by and large in the same way as in Civ3, but there are some notable differences as well. Most Units still have the basic commands: move, attack, fortify, pillage, disband, sentry, (un)board transport, skip turn. Civilization IV offers one additional standard command: explore, which lets the Unit automatically explore the map.
Another minor change is that Units now get a bigger defensive bonus the longer they are fortified. After two turns fortified, the bonus is 10%, after five turns it's 25%. That is also the maximum fortification bonus.
A bigger difference is in Unit stats: in Civ3 Units had both an attack and a defense value, in Civ4 they only have one generic Strength value. This Strength value is used both to determine the chance that a Unit hits its opponent in combat (similar to the attack/defense value in previous Civ games) and the amount of damage that is done when a hit is scored (similar to firepower in Civ2). This makes the classic Spearman vs Tank problem much less of an issue, as a Spearman not only has a much smaller chance of doing damage, it also does much less damage.
Despite the single Strength value there is still plenty of variation in the combat model, as many Units have much more unique special abilities: Spearmen have a bonus versus Mounted Units, Archers have a bonus defending Cities. Chariots and Cavalry don't get defensive bonuses, but they do have a chance to withdraw from a battle if it's going badly. With this system, every Unit has a specific role in the game and every ...
August 9, 2012, 15:49
