Damage and Defence

Defence does not deal damage. It means endurance.

Attack

Attack is how hard a unit hits. Men in the line × attack is what that formation brings to bear this round.

Note: men IN THE LINE. Two thousand archers in reserve contribute exactly nothing.

Defence

Defence deals no damage. Defence decides how hard that soldier is to kill.

The land-defence bonus you get defending your own city does the same job: it does not make your men hit harder, it makes them harder to kill.

Damage and casualties are different

Term	Meaning
Damage	Wear carried by the survivors. Nobody has died yet.
Casualty	The soldier is gone. He does not come back during the battle.

Damage accumulates

If a round does a formation less damage than its endurance, nobody dies — but the damage is not wiped. It adds to next round's, and the moment it crosses the threshold it becomes casualties.

That is why a formation ground down slowly seems to melt all at once. Nothing wipes that accumulation away; the physician does not touch it either — he only carries some of the fallen off the field as wounded.

Three multipliers, three owners

Multiplier	Whose	What it does
Land attack	The attacking player's	Increases the damage it deals
Land defence	The defending player's	Slows the damage it takes
Wall cover	The defending city's	While it stands, cuts down arrows shot over the wall

How does a blow become a casualty?

Step	What happens
1	The men in the line are multiplied by their attack.
2	The attacker's land-attack bonus is added. The defender has no such multiplier; his bonus goes into endurance instead.
3	The unit's doctrine picks the target lane; the sounder the enemy front line, the less gets through to what is behind it.
4	If the wall is standing, an arrow shot over it at the soldiers is cut down hard by its cover. A blow aimed at the wall is not.
5	Formations in the same lane share the blow.
6	The accumulated damage is divided by endurance: every whole multiple becomes a casualty, and the remainder carries over to the next round.

The figures come from the game's own content. Balance updates can move some numbers; the rules themselves are as written here.