Damage and armour
Every attack is melee, pierce or siege. A hit deals its damage plus any bonus against the target's kind, minus the target's armour against that type, and never less than 1. A Spearman hits for 4, but +18 more against cavalry, which is why a few spears stop a much dearer rider.
The Blacksmith raises attack and armour line by line, and Homespun Cloth toughens villagers. Each unit's page lists the technologies that change it.
The counter triangle
Cavalry runs down archers and siege. Spears and camels stop cavalry. Archers and swordsmen beat spears. Skirmishers hunt archers. The counter table has every row, and each unit's page says what it is strong and weak against.
Charges and braces
Mounted shock troops charge: after a run-up a Knight adds +10 to its first blow, then needs 12 s to charge again. A standing spearman braces against it: the charge is lost and the rider takes 15 damage. Keep spears still in front of your archers.
Monks
A Monk heals wounded soldiers near it and converts an enemy unit after a long channel; any new order, the target walking away or a blow to the monk starts it over. Siege engines resist conversion. Light cavalry is the quickest way to catch monks.
Siege and walls
Swords and arrows do little to stone. Rams, trebuchets, petards and bombards bring buildings down: a Trebuchet throws a 200-damage stone from 16 away but needs 4 s to set up and cannot hit anything closer than 4. Guard your siege: riders and swordsmen smash it.
A Palisade Wall costs 12 wood a segment and a Stone Wall 5 stone. Gates open for you and your allies and stay shut to enemies.
Stances and formations
Stances set how soldiers react: aggressive ones chase, defensive ones return to their post, stand ground holds still, no attack never fights, and skirmish keeps shooters at range. Formations set the shape of a march: loose, line, wedge, box and staggered. Patrol walks a route and fights whatever it meets; Retreat sends the selection home.