When attacking and taking a province there is a chance of receiving a Spoils-of-War. Most spoils allow you to increase a characters IQ, War, or Charm while increasing their loyalty to the maximum. A few spoils provide other benefits such as fast recovery from illness or protection from being captured. When attacking and taking province 10 you can obtain a normal spoils-of-war every time until you have all of the normal spoils. AI controlled rulers do not receive spoils, so allowing an AI controlled ruler to take or occupy province 10 will allow a player controlled ruler to retake the province for another spoil.
Surefire Fire
Starting a fire is often uncertain, but one time per battle a player controlled party can start a fire without fail. Choose Attack, Fire, the direction, and then press the Start button. This will start a fire even on the castle. This DOES NOT work if it is raining and can be extinguished by rain before any harm is done, so choose a good day for a surefire fire. If a player controls both parties in the battle then each party gets one surefire fire.