Tactics of War in Rome: Total War II

Most strategy guides talk a lot about advanced unit types, but unless you play very slowly you will only get them in the end game, when you're so strong that it doesn't really matter that much.

A very important unit type are peasants, which you should use exclusively for garrisoning, but never for battles. Peasant garrisons are half the upkeep costs of the weakest battle units, so use them. If you have some spare peasants you can take them with your army so they can serve as an occupying force for the captured settlements, while your real forces go forward. Or maybe if someone needs to hold battering rams and you have pure-cavalry army, but that's already getting somewhat dubious.

One of the nicest things about Rome: Total War is richness of unit types and tactics you can develop with different combinations of unit types against different combinations of enemy unit types.

Many tactics can be formed around phalanges. First you take a wall of any units capable of forming a phalanx, which most factions can get almost immediately. Then you make either your opponent run into the wall of spears, or attack your opponent with this wall. If you set guard mode on your units will try to keep the wall of spears, if you set it to off they will break it to attack the enemy. Either can be useful depending on circumstances.

Even a phalanx formed with very cheap units can kill most of enemies. Non-phalanx infantry, and light cavalry will simply get massacred. With heavy cavalry, elephant, and chariots it's not that simple. Depending on your and their strength they might be killed by your phalanx (instant win) or break it (instant lose), but often they will simply get entangled in it without getting killed. Now it's time to attack, either with adjacent phalanx unit, or even better with your cavalry attacking from a side or a back. You will have some loses in your cheap phalanx, but you'll kill a much more expensive heavy cavalry unit this way, for a major win.

To fight with other phalanx you simply form a pushing match. If you have stronger phalanx, especially one with longer spears, you can outstab the enemy. If not, just attack the enemy phalanx with some cavalry while they cannot move.

The main problem with phalanges is that they are very vulnerable from flanks and back, so you want to keep some cavalry, or at least some non-phalanx infantry on both wings. Not only will it protect your phalanx, they can attack and destroy any enemy captured by it.

If enemy has some cavalry, you might want to take all your cavalry, charge into his, and try to destroy it before the infantry battle begins. Cavalry has very high charge bonuses so by properly maneuvering you can do disproportionate damage even without very strong units. If they rout, don't follow but go back to wings of your formation - you won't catch horses with horses, and your cavalry is too important to waste just yet. Even if the enemy reforms they won't have much morale left and you can rerout them later with a simple charge.

It's important to have cavalry superiority, even though the cavalry won't win the battle for you. If you charge at a phalanx, or even straightforward melee infantry, you're going to suffer heavy loses. Cavalry is strong because of high charge bonus, if they're entangled they suddenly become very vulnerable. There are some units you can safely charge at - missile units like archers/bowmen, peltasts/velites/skirmishers etc.; very light infantry like rebel peasants; other cavalry units, including generals (who are weak without their bonus charge); and later artillery units. Charging at anything else means high loses even with relatively heavy cavalry, and is outright suicidal for light cavalry. Even if some unit is weak, you can still suffer if there's a strong unit in its proximity. So obviously bowmen shouldn't be left without protection.

Another important thing you can do with cavalry is killing off routing infantry units. The difference between defeated army suffering 30% loses refilled in the first visit to nearby city, and 90% loses that are impossible to refill comes from your cavalry. Normally infantry cannot catch routing infantry, and cavalry cannot catch routing cavalry, so the only kind of massacre you will be able to do is cavalry massacring routing infantry. Even the cheapest light cavalry is very important just for this purpose.

If you have cavalry superiority you can get some missile units, or later some artillery. They are very weak against cavalry, and it's not too easy to protect them using just infantry after the chaos of the battle starts. Your tactics depends on range of your missile units, so usually it makes no sense at all to have multiple kinds of missile units in the same army. Either take all bowmen, or all peltasts, or all onagers, or some other consistent army.

Missile units cause free damage to your opponents. They can try to stand it out until you run out of ammo and suffer heavy casualties, or else they'll be forced to attack you on your terms. If the enemy has no cavalry and no missile units (or you just killed them with your cavalry), you can even send your missile units in skirmish mode way in front of your main units to pepper them with arrows and javelins. Normally however you want to keep them close to your units, either behind your main infantry line, or just in front and then making them fall back when the attack finally happens.

Missile troops alone are not going to win the battle. But with enough damage the enemy will be losing morale and will rout more easily. After some of the enemy starts routing the battle is pretty much won, and just use your cavalry to kill off what's left. Missile units are also quite useful at finishing off routing units.

There are a few more tactics you can try. Romans have strong infantry units that throw javelins before attacking. It's like an ok missile troop and a good melee troop in one unit. If you stand against enemy phalanx with Roman infantry try splitting your troops and attacking from flanks. It might work just fine.

Chariots are like heavy cavalry except you can have them very early in the right faction like Egypt and Seleucids. They have even lower defense than normal cavalry, so try charging through enemy unit to the other site, not on enemy unit. Also, never let enemy missile units fire at your chariots, or anybody to attack a standing chariot. It takes some practice to learn how to use chariots properly, but it's fully worth the effort.

If you have mixed heavy and light cavalry and want to charge a strong unit, charge with your heavy cavalry first, immediately followed by the light cavalry. This reduces your loses a lot. On the initial charge will still be capable of defending itself, so a heavy charge is needed. Just afterwards it will be completely disorganized so even light cavalry will be able to make a kill.