+1 combat result for having more Unit Strength than your enemy.
When a group of warriors is facing uneven odds, it is considerably more likely to lose heart. Likewise, knowing that you outnumber the foe can be a great morale boost. If your unit has a higher Unit Strength of your enemy, add +1 to the combat result. If multiple units are involved in the same combat, calculate the combined Unit Strength of all units involved on both sides to determine which side might get the Outnumber bonus.