I recently purchased this game, and I'm having fun with it, with one exception, with the latest patch (and I don't know if this is limited to multiplayer, as that's all I've played), combat seems incredibly broken, ie musketmen and cavalry commonly taking out marines easily (as well as the odd archer), SAM units being wiped out by helicopters (claims they are supposed to have +50% bonus against helis), my friend's walled cities being taking by one cavalry group (wiping out defenders), we were playing a game on a huge map with 6 AI civs at noble difficulty. We were both levelling our units when possible, were up to date with technology, it's a shame, because what's the point of progressing through the unit tree if an early cavalry unit can cut down your marines etc.? Do the AI civs receive bonus experience at the higher difficulty levels or something? I greatly appreciate any insight you can provide. Thank you in advance.

the AI does NOT receive bonus in combat. It has bigger armies of better units as you progress into level, but not anything like specific bonuses for combat.

Did you consider collateral damage? With enough of it, you can take redcoat's defended cities with macemen.

if you have 10 battles with odds of winning 90% for each battle, chances are that after 10 battles you will lose that unit. he might get lucky and last 1000 battles, but the law of averages dictates that on average a unit with 90% battle odds will last only 10 battles.

The AI was probably using catapults/trebuchets/cannons/artillery/whatever to get collateral damamge, which mean a full strength Cavalry (15) can take out a half strength Marine (12/24)...

What promotinos where you using?

I've destroyed armies of Grenadiers with Musketmen because i had cannons. It all depends HOW you use your units.

Gunships are equal against sam's if there are no other factors in play.. ofc promos / terrain / colleteral damage(or planes) can easily tip the favour...

Yep, the AI does NOT receive bonus in combat. A Spearman can (rarely) defeat a tank.


This epitomizes that bad luck: :spear:

Welcome to the Forums eviljeff334. :beer:

Yep, the AI does NOT receive bonus in combat. A Spearman can (rarely) defeat a tank.


This epitomizes that bad luck: :spear:

Welcome to the Forums eviljeff334. :beer:

I think the 2x production it has on deity qualifies as a bonus, but in ANY ONE COMBAT, the game works exactly the same for the AI as the human on all levels.

Still, when they produce double the units, you are twice as likely to lose a 1% battle as you are on noble level, just because you're fighting twice as many units. This can easily affect perception.

Still, when they produce double the units, you are twice as likely to lose a 1% battle as you are on noble level, just because you're fighting twice as many units. This can easily affect perception.

But how often do you hear Deity players moan about unfair combat results? ;)

eviljeff334, welcome to the forums ;)

It looks that you still need to know about combat in Civ IV:

1- Promotions

Some promotions lines in civ IV were designed to boost the defensive strengths of the units bearing it in certain terrains. They are mainly ( if I hadn't forgot any ) the Guerrilla line ( more defense on hills ), Woodsman ( more defense on forest/jungle ) and City garrison ( boosted defense on cities ).

Besides that , there are other promotions that act as strenght boosters vs a certain type of units: Cover ( against archery class units ( archers, longbows and crossbows ) ), Shock ( vs melee ), Pinch ( vs gunpowder units ), formation ( vs mounted units ), ambush ( vs armoured ) and interception ( vs air units ).

To end there are promotions that somewhat boost the strenght of a attacking unit vs a certain terrain ( in fact, they decrease the defender's strength ), mainly they are the city raider line ( against units in cities ), Woodsman III ( vs units on forests/jungles ) and Guerrilla III ( vs units on hills ).

As you can imagine, the use of promotions can make a huge diference in the outcome of a battle. I suggest you to give a good look at the civilopedia in-game for more reference

2-Cultural and terrain defense

Fisrt of all, some terrains natively give defensive bonuses in Civ IV: forests ( + 50% strenght ), hills ( +25% ) and coast ( + 10% ). If the attacker has to drop of a ship to attack or to cross a river, it suffers a penalty for that too, denied by the amphibious promotion. to add, most of the units gain a defensive bonus if you fortify ( not sleep ) them for a certain ammount of turns.

On cities: you should already had noticed a number in top of the cities name bar like "+125%" . That number is the city bonus defense, a mix between city improvements that give extra defensive proposes ( like walls and castles ) and the culture level of the city. That number is added to the other defensive multipliers and it can boost significantly the defensive strength of a unit ( + 100% means that it is like you're facing a unit with the double of the strength of the original one ). You can reduce or nulify this bonus using siege equipement and using the bombard action ( the one that looks like a bullseye )

3- Collateral damage

Some units have the ability to make damage to more than one unit at the time if they are all on the same time. Thisability is called collateral damage and normally ( not always ) is a caracteristic of siege units. This leads to a technique heavily used in civ IV , that is to sacrifice some siege units vs a group of enemy units ( normally refered as stack ;) ) to make them weaker and then to use other units to kill the weakened units. This is probably the more widespread way of fighting in Civ IV and you should definitely give it a try.

Just to end, there is a good way to know the probablilities that you have in a fight: pick the unit you want to use to attack and presst the ALT button while hovering the mouse pointer over the target unit. this will give you all the attacking and defensive bonuses and the probability of you winning that fight. That surely helps you to make a better judgement of the fights you want/need to do . And remember always that in Civ IV , all the units can lose a fight regardless of the weakness of the enemy units ;)

This is not a exaustive guide, but it is a good place to start. You can find more detailed information both in the in-game civilopedia and in the War academy of this site.

Gunpowder units ignore walls. That cavalry that took out your friend's walled city ignored those walls entirely, so that may be why you're surprised.

This is obvious, but I want to state it just in case: over the course of one or two battles, a vastly superior unit can be severely damaged, which will affect it's odds in combat.

While it isn't common for a 15 strength unit to take out a 24 strength one, it is possible (maybe the cavalry caught the marines asleep? =P) but I have a feeling that what you are experiencing is a marine that has taken out a few guys and suffered damage in the process, then loses to a mediocre unit.

The combat system between the patches and expansions are different from vanilla Civ. Which are you playing?

In vanilla Civ (first one, out of the box, and no patches), your marine has a base strength of 24. If he fights even a 2 strength warrior there is a small chance he will take a little damage. If a marine fights enough warriors (we're talking a lot here) he will eventually have LESS than 2 strength, and the warrior may win.

We have all been there... 20 strength infantry losing to a 12 strength rifleman.

The combat engine may make more sense if you discover the combat log, which will report most of what's going on in combat.

It's neither pefrect nor easy to interpret, but most of the answer are there....

Thanks for the insight, though I do understand promotions and terrain, it just seems wrong that cavalry can take out a marine (and this was at full strength), then really, what's the point of creating the more advanced units if the AI is just going to promote the heck out of their earlier units and destroy you anyway? I know certain battles are a no-brainer, like a tank versus infantry, but one time a defending spearman in a city took out my full strength (and promoted) marine - I mean, come on, that's just a little ludicrous. My friend was literally only winning maybe 1/10 battles when he was fighting their units (many of them musketmen and other earlier units), and this was with advanced and promoted ground units. I appreciate the insights provided, and I apologize for belaboring this, it's just frustrating.

Oh, also, I am playing plain Civ IV, no expansions, patched to the latest (AFAIK) version, 1.74

I wouldn't be surprised if the patched changed the combat somewhat, because my friend mentioned that he had played two full single-player games to victory (with 6 other AI Civs) at a higher difficulty with no problems (we both patched to the latest version before we began multiplayer).

Yep, the AI does NOT receive bonus in combat. A Spearman can (rarely) defeat a tank.


This epitomizes that bad luck: :spear:



I think I saw that in a kung-fu movie. It's totally plausible if you're 1337. :goodjob:

I know certain battles are a no-brainer, like a tank versus infantry, but one time a defending spearman in a city took out my full strength (and promoted) marine - I mean, come on, that's just a little ludicrous.

"It's not FUN" is a totally fair complaint.

There are sort of two questions/criticisms available here, and it may be worth distinguishing between the two. One question is "Are the displayed combat odds reasonably representative of the actual probabilities"; another is "are the actual probabilities reasonable".

For the latter question, that's going to be a matter of taste. Historically, combating generation N troops with generation N-1 technology has been Very Bad Luck[tm], so you can justify writing your engine to reflect that. For a casual gaming audience, that can easily fall behind the UI in technology, that would likely be an unfortunate choice. So the designers (as I understand it deliberately) went another direction.

(There were similar choices made about early rushing, and defending against early rushing.)

If you've been patched up to 1.74, you actually have acquired a change in the combat mechanic that would affect spearman vs marine. Alas, that change went the other direction, if I'm remembering rightly - a search of the forums may confirm that at one point STR 4 tanks were weaker than STR 4 spears.

As for the former point - you can experiment a bit with combat in the world builder - stack attacks and so on, to get a sense for how well the displayed odds match the actual odds. I wouldn't over invest in it - unless you have a good feel for statistics, or the patience to run a LARGE number of trials, its fairly easy to be fooled by a run.

There is some debugging built into the RNG system - if you have a hand for such things, you may be able to collect all of the die rolls and get a measure of how "fair" the dice really are. I don't think you are going to find anything, but it may prove instructive.