With two exceptions, one of which is slaying the final boss is the same battle. In my experience thieves make for the worst lords because if you actually use their stealth abilities, they are probably on their own and thus vulnerable to getting ganged up upon.

Prisoners have a chance of escaping you can knock them out to prevent this, but if you knock them out enough times prisoners auto die. Where you can either try ransoming them for money, you can try interrogating them or torturing them for info (both have a chance of killing the unit.), and you can execute them. Where if you win the battle you'll keep the enemy as a prisoner. They can go invisible (although units have a chance to detect them) they can attempt to spy on other parties, they can attempt to steal from other parties, and in battle they can attempt to capture a champion. We have ranged attacks, and offense and defense in the middle of warriors and mages. (When this happens depends on what faith we choose. We start out weaker then the warrior, but become stronger later in the game. Mage is the standard, we have crap for offense and defense, but we get magic. This ability gives a slight attack buff, and maybe a slight defense buff to all your units in that battle. However all warriors have a once a day Rally ability. Warrior is the standard, we have decent offense, decent defense. We can go to a higher level, and we are even better then equivalent level 'champions' of the same type. As a lord, we are the most powerful unit (or one of the) most powerful units in the faction.

Lords of magic map