I've got what I think is going to boil down to a war on my eastern front. China is attempting to press my territorial boundaries and has been building new settlements along my eastern front. Naturally, I've also been attempting to build new settlements there as well as moving troops. Quite a few of my hills overlooking the front now have forts on them. The downside is that China is ranked #1 in the scores, and I'm really not looking forward to going up against them in a war. Worse, China is already "cautious" towards me, so we're only 1 or 2 steps away from hostilities.

The first map shows the overall strategic situation. You can see that I have a very wide front with the Mongolians (dark yellow) to the southwest, a narrow front with the Incas (medium yellow) up north, and a potentially wide front with China (purple). An adequate description of this situation is "between a rock and a hard place". There's a very good chance that I could find myself fighting a multi-front war with multiple AI civilizations.


The next map shows resource distribution. You can see that there is copper, iron, marble down in the SE of my empire, which is why I'm pressing so hard to setup shop down there. While I have copper and iron in other parts of my empire, it's always good to have extra sources and to deny their use to my enemies. My only "safe" copper mine is up in the NE near the Incas (near Nezumi) and my only "safe" iron mine (near Old Kyoto) is pretty much right on the border with the Mongolians.


Securing those 2 iron mines and the copper mine down in the SE is what will keep me from going under over the long term. There's another copper mine up in the NE part of the eastern front (near Izumo) that is also pretty strategic.

The next 2 images are high altitude screenshots of my eastern front. I've removed all labels from the map so that it's easier to see terrain, cities and fortification points. This is a pair of screenshot stitched together to make it easier to see the entire area in question.


Here's a marked up map. Green blocks are my cities. Red blocks are (future) enemy cities. Yellow six-pointed stars are where I have fortifications. Yellow stars that are not filled in are planned future locations for fortifications. It's a very heavy defensive concentration. The purple star is where I will place a fort once I take their westernmost city in a smash attack.


The rules for combat in Civ4 are somewhat simple. The terrain that the defender is standing on may give bonuses to the defender. Whoever initiates the attack is always considered the attacker and gets no terrain bonus (yes/no/maybe?) during the assault. So for the following situations where the attacker is attacking a defender:

(Location / Bonus)
Hill = +25%
Hidden in Jungle/Forest = +50%
Inside a fort = +25%
Across a river = +25%

So for a defender, the best place to hide is either in a jungle/forest, or on top of a fortified hill. Some units get additional abilities that grant them even more defensive power when stationed in a city or on a hilltop or in forest/jungle. These force multipliers allow 3STR archers to take on 5STR axemen and win. Plus, there's a bonus for digging in ahead of time (+5% per turn, up to +25% max). Cities can also build walls and other fortifications that add defense bonuses.

So, almost all of my forts are located on hills. A lot of my cities end up on hills as well. Mountain tiles cannot be crossed by units and serve as a natural defense. Putting your units on the safe side of a river provides natural defense.

Notice that the AI does not have any forts. I'm not sure if this is a bug in the AI, or if the AI simply won't use them.

As I hinted earlier, if the China AI decides to start a fight, I have a few preliminary plans.

A) Stop their assault in the NE. I expect that Izumo in the NE is a likely target. It's in an extended position and there are sizeable cities within a short march. The (2) forts and the city are manned with at least one of each type of fighting unit that I can muster (knight STR10, crossbowman STR6, longbowman STR6, pikeman STR6). I'll make sure that all squares surrounding Izumo are covered in roads to allow my troops quick movement on/off an attacker's tile. Since Izumo is built on a hill, the defensive troops all have the +25% hill bonus.

Plus, if I can extend my cultural borders 1 square to the south, there's another hill where I can place a fortification and add a first line of defense.

B) Stop an attack based out of Baoding (their western city). If I'm weak, it's here in the middle. Yokohama is a straight shot across some plains and my defensive units would have to leave their hilltops to get within strike range of the incoming army. Knights are going to be a key part of any defense down in that area (as is covering the terrain in a road network).

C) Stop a southern attack (unlikely). If they come via the southern river valley, they're in for a long march.

D) Retaliation plan #1. Raze any improvements in the area between Shadong and Kaifeng up north. Hit and run raids, avoiding battle whenever possible. Probably with knights and pikeman. There are half a dozen tiles that the AI has improved and is working within strike range of my Izumo units.

E) Retaliation #2. Take Baoding. This requires staging of catapults at the forts to the NW and S of Baoding. Their town is still lightly guarded, but it will take some serious firepower to overcome a grenadier STR12 unit that has both city defense promotions.

The usual plan is to outfit the catapults with barrage ability and then suicide them against the stack of defenders in the city. The barrage ability results in damage to other units in the stack, not just the one that attempts to defend against your attack. Each suicide attack lowers the STR of the defenders until eventually I can send in my infantry to take the city streets.

Additional units will need to take up positions on the hill east of Baoding to repel reinforcements. This is a nicely forested hill that provides a hefty +50% bonus to defense and all of the surrounding tiles are denuded of forest (or were desert to begin with).