Units make up your civilization's soldiers, traders, workers, and explorers. Units gain experience by performing tasks such as combat, spell-casting, exploring ruins and lairs, and so on. Each experience level allows them to take a promotion that improves their abilities. At certain levels, units can pick specializations: at level 4 they pick a Discipline which unlocks new promotions and grants new abilities, and at levels 8 and 15 they pick Prestige Classes within their Discipline which grants them more special abilities.Unit Types:
Melee - Offensive units. They can specialize in many different areas, and form the backbone of most armies.

Ranged - Defensive support units. They can specialize in firing volleys at nearby stacks, and defensive strikes on units that attack their stack.

Mounted - Mobile offensive units. They can specialize in increased mobility, and withdrawing from battle.

Recon - Mobile skirmisher units. They can specialize in scouting terrain, taming animals, and prioritizing weak/support units for assassination.

Naval - Sailing units. They can specialize in acting as transports, blockading rival ports, attacking at range, and increased mobility.

Siege - Offensive support units. They can specialize in destroying city defenses, attacking at range, and causing collateral damage.

Arcane - Ranged support caster units. They cast arcane spells, generate spell effect auras, and create mana nodes.

Disciple - Melee support caster units. They can call down divine miracles, heal units, and spread religion.

Specialist - Non-combatant support units. They have a variety of economic and military special abilities.
Disciplines:
Ambush Discipline - Equips Martial and Exotic Weapons. +20% Hill/Forest Strength and double speed in hills/forests.

Leather grants higher Quality Equipment bonuses.

Vengeance Discipline - Equips Martial Weapons. Attacks weakest unit in a stack.

Leather grants higher Quality Equipment bonuses.

Archery Discipline - Equips Martial and Exotic Weapons. +1 Ranged Strength.

Wood grants higher Quality Equipment bonuses.

Skirmish Discipline - Equips Martial Weapons and Heavy Armor. +20% Withdrawal Chance.

Wood grants higher Quality Equipment bonuses.

Offensive Discipline - Equips Martial Weapons and Heavy Armor. +10% Strength. +10% City Attack.

Metal grants higher Quality Equipment bonuses.

Defensive Discipline - Equips Heavy Armor and Exotic Armor. +20% Defensive Strength.

Metal grants higher Quality Equipment bonuses.

Divine Discipline - Equips Heavy Armor. +20% chance to convert defeated living units.

Metal grants higher Quality Equipment bonuses.