Battles occur during the night, after you press the End Turn button. There are many factors that influence the outcome, and some of it is down to pure luck. However, paying attention to detail can bring its rewards.
During battle, each soldier gets opportunity to attempt killing one of his opponents. Lords get several, depending on their courage and experience - Dragons, Werewolves, and Wise receive even more than other races.
From the pool of all (remaining) attempts, one is chosen at random, to define the attacker. If a garrison is present, it will automatically become the attacker, until all its attempts are used.
Attacker then picks up his target. Up to 200 rounds (army sizes allowing) will now be fought only between these two, the attacker randomly chosen among them each round.
If there are several possible targets for the attacker, one is chosen randomly, weighted by target size. There are several factors that influence target size - number of soldiers (with riders twice the size of warriors), race's physical size (Giants are bigger targets than Dwarves, for example), terrain (Dwarves in mountains and Fey in forests are smaller targets then normal), and importance (lords are much bigger targets than ordinary soldiers; Wise, kings and heroes even more so). Garrisons are small targets, and soldierless lords in friendly garrisons even smaller.
In advanced games, relationships might influence targeting, lords picking on those in the enemy lines whom they find the most hateful.
The success of the attempt is determined by comparing battle ratings of attacker and defender in question, and the terrain they're fighting on. Battles on plains are bloodier and those in mountains and forests less so. Also, some races are harder to kill, like Dragons and Werewolves, and Skulkrin at henges and Wise at towers. Heroes are as hard to kill as dragons.
In advanced games, lord's temperament and relationship towards his target add to or take from the chance for a successful hit.
If the attacker succeeds, defender takes damage. If the defender has any soldiers left, a soldier dies, and if the soldier hasn't made his attempt at the enemy yet, the attempt is lost. If a lord is soldierless, but mounted, there's a 50% chance that he'll only be unhorsed. If the lord is without a horse, he dies. A hit by a Foul king or hero has a small chance of stripping the defender of courage instead of killing anyone.
This, in effect, is how good someone is at fighting. It's calculated separately for the lord, his riders and his warriors, because their strengths are important part of the calculation, as are courage and experience. The higher the difference is between attacker's and defender's battle rating, the greater is the chance for an attempted hit to succeed.
Many factors influence the actual battle rating:
- riders are usually better fighters than warriors
- some races fight better than others
- king's and hero's troops get a better rating
- presence of the king on a battlefield increases battle rating for his side, especially for lords and soldiers of his own race
- troops sheltered at a friendly stronghold receive a bonus
- the mix of terrain, race, and soldier type modifies the rating
- in advanced games, a lord's siegecraft and training will further modify it
Allies can be very helpful in battle. They represent valid targets, but, if it's your turn, don't suffer any damage, since they already fought on their own turn. Let's take a closer look at this. Suppose we have players A and B who are allied, and player C, their enemy.
- On his turn, player A attacks player C. We have a normal battle resolution.
- Then, player B attacks player C. Only B's troops attack player C, because player A already attacked on his turn (1). But both player A's and player B's troops are valid targets for player C. However, player A doesn't take any damage, because, as before, A already took damage on his turn (1).
- It's player C's turn and he decides to continue his battle. Both A and B fight against him, and both take their share of damage.
- Player A's turn is just the mirror image of player B's: only his troops attack C, his and B's are valid targets, but B's don't take damage - they received it on B's turn (2).