In the heat of battle troops often don't respond as you, their commander, might want them to. Faced with terrifying supernatural foes their courage may fail, or they may simply be too dim to understand the orders they have been given. The hatred engendered by age-long feuds can overwhelm military discipline and leave troops overcome by bloodlust against their ancestral foes. Certain warriors can be so overwhelmed by berserk fury that they will charge into battle regardless of any plan or order.
As commander of your army it is your duty to know about these things and take them into account in your plans. If you do not you may find that you are defeated before you even begin!
The psychology rules represent these factors in the game and call upon the player to make occasional tests to determine whether his troops are affected by adverse psychology. All psychology tests are made in the same way, so we'll describe the procedure first before we look at the individual psychological factors.
When taking psychology tests roll 2D6 and compare the result to your leadership (Ld) value. If the result is less than or equal to the unit's leadership score the test is passed and all is well. If the result is greater than the unit's leadership score then the test is failed.
Note that in the case of cavalry, chariots, and heroic individuals riding monsters it is the rider's leadership that is used and not the mount's or the monster's. If a chariot has several crew, use the highest value.