In Castles and Crusades I can't find anything that dictates when an NPC or Monster is dead and have always just assumed that once they get to 0 HP they are dead. I came across something, I can't remember where, that states a PC isn't actually dead until -6 HP and goes into an unconscious state at 0 HP.
Why isn't it the same for NPC's and Monsters? Is this more of a DM discretion item?
If it isn't the same, is there something in the rules against allowing NPC's and Monsters to abide by the same rules as PC's and what is the reasoning?
The party "kills" an orc warrior, resulting in -3 HP. An orc shaman is in the woods nearby and heals the warrior to full health, waking him up from the unconscious state, and returning him to battle. He catches the party off guard and is now an extra opponent, possibly harming party members that don't realize the "dead" orc is back in action.