Each unit has an individual minimum stat, but can be adjusted, dependent on that particular unit's stat maximum. The number of allocable Stats increase with a unit's Rank.
Armor[]
Armor blocks damage. Your strength - their armor = damage.
Strength[]
Strength is both damage and health. If strength drops to 0 the unit falls unconscious.
Willpower[]
Willpower is spent to move further, hit harder, and perform your ability, but does not replenish.
Exertion[]
Exertion is the amount of Willpower you can use on any given action.
Break[]
Break is the amount of direct damage you can naturally do to an enemy's armor.