Escape/Capture!
If you lose a battle, it is usually the case that all officer prsent are automatically in the winner's force.
If the roll is 1 - 20 then you are free, if it is 21 - 50 then you are auto captured and placed into the unit of the capturing officer, you may try to escape every 12 hours and we will roll the same thing to tell you if you escaped.
Defecting!
Okay, in the game we see Zhou Fang defect to Wei in the Battle of You Ting.
But in reality, not all your troops will join you once defected, so a roll will take place (100 to the number of your troops). Result is how many you keep, the remainder go back to original ruler.